Bio

Bio


Mintu Turakhia M.D. M.A.S. is a cardiac electrophysiologist, outcomes researcher, and clinical trialist. Dr. Turakhia has an active, highly-funded multidisciplinary program in atrial fibrillation, where uses large datasets to examine quality, outcomes, and risk prediction for heart rhythm disorders. As the Executive Director of Stanford’s new Center for Digital Health, he is the principal investigator of several multi-center trials to test digital health tools and wearable devices to screen and manage heart rhythm disorders. In his clinical role as Director of Cardiac Electrophysiology at the VA, Dr. Turakhia performs invasive procedures such as catheter ablation and device implantation to treat heart rhythm disorders. Dr. Turakhia is a Fellow of the American Heart Association, American College of Cardiology, and Heart Rhythm Society.

Clinical Focus


  • Arrhythmias, Cardiac
  • Cardiology (Heart)
  • Death, Sudden, Cardiac
  • Catheter Ablation
  • Atrial Fibrillation
  • Implantable Defibrillators
  • Tachycardia, Supraventricular
  • Clinical Cardiac Electrophysiology

Academic Appointments


Administrative Appointments


  • Co-Chairperson, VA Health Services & Research Career Development Conference (2009 - 2010)
  • Chair, Writing Group, American Heart Association Telemetry Latency Advisory (2010 - Present)
  • Member, Young Clinicians and Investigators Committee, American Heart Association Council of Quality and Outcomes Research (2010 - Present)
  • Member, Electrocardiography and Arrhythmias Committee, American Heart Association (2009 - Present)
  • Cardiac Electrophysiologist, Stanford Hospital and Clinics (2008 - Present)
  • Director, Cardiac Electrophysiology, Palo Alto VA Health Care System (2008 - Present)

Honors & Awards


  • E. William Hancock Faculty Teaching Award, Stanford Division of Cardiovascular Medicine (6/2010)
  • Department of Medicine Teaching Award, Stanford Department of Medicine (12/2010)

Professional Education


  • Professional Education:University of California San Francisco Registrar Office (2008) CA
  • Professional Degree, Biodesign, Faculty Fellow (2015)
  • Board Certification: Cardiovascular Disease, American Board of Internal Medicine (2006)
  • Board Certification: Clinical Cardiac Electrophysiology, American Board of Internal Medicine (2009)
  • Fellowship:Univ of California San Francisco (2008) CA
  • Fellowship:Univ of California San Francisco (2006) CA
  • Residency:Brigham and Women's Hospital Harvard Medical School (2003) MA
  • Internship:Brigham and Women's Hospital Harvard Medical School (2001) MA
  • Medical Education:Univ of California San Francisco (2000) CA

Community and International Work


  • Research Chair, Mountain View, CA

    Topic

    Cardiovascular risk in South Asians

    Partnering Organization(s)

    South Asian Heart Center, El Camino Hospital

    Populations Served

    South Asians

    Location

    Bay Area

    Ongoing Project

    Yes

    Opportunities for Student Involvement

    Yes

Research & Scholarship

Current Research and Scholarly Interests


Dr. Turakhia has an active clinical research program, with funding from AHA, VA, NIH, the medical device industry, and foundations. His research program aims to improve the treatment of heart rhythm disorders, with an emphasis on atrial fibrillation, by evaluating quality and variation of care, comparative and cost-effectiveness of therapies, and risk prediction. Dr. Turakhia has extensive expertise in using large administrative and claims databases for this work. His TREAT-AF retrospective study of over 500,000 patients with newly-diagnosed AF is the largest known research cohort of AF patients. He has served as study PI or chairman of several prominent single- and multicenter trials in atrial fibrillation, investigational devices for electrophysiology procedures, digital health interventions, and sensor technologies.

His other research interests include technology assessment of new device-based therapies and the impact of changing health policy and reform on the delivery of arrhythmia care. Dr. Turakhia is a Fellow of the American Heart Association, American College of Cardiology, and Heart Rhythm Society.

Teaching

2018-19 Courses


Stanford Advisees


Graduate and Fellowship Programs


Publications

All Publications


  • Practice Variation in Anticoagulation Prescription and Outcomes after Device-Detected Atrial Fibrillation: Insights from the Veterans Health Administration. Circulation Perino, A. C., Fan, J., Askari, M., Heidenreich, P. A., Keung, E., Raitt, M. H., Piccini, J. P., Ziegler, P. D., Turakhia, M. P. 2019

    Abstract

    BACKGROUND: Device-detected atrial fibrillation (AF) is associated with increased risk of stroke. However, there are no clearly-defined thresholds of AF burden for which to initiate oral anticoagulation (OAC). We sought to describe OAC prescription practice variation in response to new device-detected AF and the association to outcomes.METHODS: We performed a retrospective cohort study using data from the Veterans Health Administration linked to remote monitoring data that included day-level AF burden. We included patients with cardiac implantable electronic devices (CIED) and remote monitoring from 2011-2014, CHA2DS2-VASc ≥2, and no prior stroke or OAC receipt in the preceding 2 years. We determined the proportion of patients prescribed OAC within 90-days following new device-detected AF across a range of AF thresholds (≥6 minutes to >24 hours), and examined site variation in OAC prescription. We used multivariable Cox proportional hazards regressions to determine the association of OAC prescription with stroke by device-detected AF burden.RESULTS: Among 10,212 patients with CIEDs, 4,570 patients (45%), 3,969 patients (39%), 3,263 patients (32%), and 2,469 patients (24%) had device-detected AF >6 minutes, >1 hour, >6 hours, and >24 hours, respectively. For device-detected AF >1 hour, 1,712 patients met inclusion criteria (72±10 years; 1.5% female; CHA2DS2-VASc 4.0±1.4; HAS-BLED 2.6±1.1). The proportion receiving OAC varied based on device-detected AF burden (≥6 minutes: 272/2,101 (13%); >1 hour: 273/1,712 (16%); >6 hours: 263/1,279 (21%); >24 hours: 224/818 (27%)). Across 52 sites (N=1,329 patients), there was substantial site-level variation in OAC prescription after device-detected AF >1 hour (median: 16%; range: 3%-67%; median odds ratio: 1.56 [95% credible interval 1.49-1.71]). In adjusted models, OAC prescription after device-detected AF >24 hours was associated with reduced stroke risk (HR 0.28, 95% CI 0.10-0.81, p=0.02), although the propensity-adjusted model was significant when AF lasted at least 6 minutes.CONCLUSIONS: Among Veterans with CIEDs, device-detected AF is common. There is large practice variation in 90-day OAC initiation after new device-detected AF with low rates of treatment overall, even for episodes >24 hours. The strongest association of OAC with reduction in stroke was observed after device-detected AF >24 hours. Randomized trials are needed to confirm these observational findings.

    View details for DOI 10.1161/CIRCULATIONAHA.118.038988

    View details for PubMedID 30880434

  • Comparison of QT Interval Measurement Methods and Correction Formulas in Atrial Fibrillation. The American journal of cardiology Tooley, J., Ouyang, D., Hadley, D., Turakhia, M., Wang, P., Ashley, E., Froelicher, V., Perez, M. 2019

    Abstract

    Antiarrhythmic drugs used in atrial fibrillation (AF) cause QT prolongation and are associated with torsades de pointes, a deadly ventricular arrhythmia. No consensus exists on the optimal method of QT measurement or correction in AF. Therefore, we compared common methods to measure and correct QT in AF to identify the most accurate approach. We identified patients who had electrocardiograms done at Stanford Hospital (Stanford, California) between January 2014 and October 2016 with conversion from AF to sinus rhythm (SR) within a 24-hour period. QT intervals were determined using different measurement methods and corrected using the Bazett's, Framingham, Fridericia, or Hodges formulas for heart rate (HR). Comparisons were made between QT in a patient's last instance of AF to SR. Computerized measurements were taken from 715 patients. Manual measurements were taken from a 50-patient subset. Bazett's formula produced the longest corrected QT in AF compared with other formulas (p <0.005). Measuring QT as an average over multiple beats resulted in a smaller difference between AF and SR than choosing a single beat. Determining QT from a 5-beat average resulted in a QTc that was 19.0ms higher (interquartile range 0.30 to 43.7) in AF than SR. After correcting for residual effect of HR on QTc, there was not a significant difference between QTc in AF to SR. In conclusion, measuring QT over multiple beats produces a more accurate measurement of QT in AF. Differences between QTc in AF and SR exist because of imperfect HR correction formula and not due to an independent effect of AF.

    View details for DOI 10.1016/j.amjcard.2019.02.057

    View details for PubMedID 30961909

  • IMPACT OF PATIENT FRAILTY ON ONE-YEAR MORTALITY ACROSS CHA2DS2-VASC SCORES: FROM THE TREAT-AF STUDY Pundi, K., Perino, A., Fan, J., Askari, M., Heidenreich, P., Turakhia, M. ELSEVIER SCIENCE INC. 2019: 539
  • EFFICACY OF A CENTRALIZED, BLENDED ELECTRONIC, AND HUMAN INTERVENTION TO IMPROVE DOAC ADHERENCE: THE SMARTADHERE TRIAL Turakhia, M. P., Sundaram, V., Smith, S., Ding, V., Ho, P., Kowey, P. R., Piccini, J., Foody, J., Birmingham, M., Ianus, J., Rajmane, A., Mahaffey, K. ELSEVIER SCIENCE INC. 2019: 510
  • HOW MUCH ATRIAL FIBRILLATION IS TOO MUCH? TREATMENT BENEFIT OF ANTICOAGULATION BASED ON THRESHOLD OF DEVICE-DETECTED AF Perino, A., Fan, J., Askari, M., Heidenreich, P., Keung, E., Piccini, J., Ziegler, P., Turakhia, M. ELSEVIER SCIENCE INC. 2019: 290
  • Atrial fibrillation burden, progression, and the risk of death: a case-crossover analysis in patients with cardiac implantable electronic devices. Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology Piccini, J. P., Passman, R., Turakhia, M., Connolly, A. T., Nabutovsky, Y., Varma, N. 2019; 21 (3): 404–13

    Abstract

    AIMS: Atrial fibrillation (AF) is associated with increased mortality, but the temporal relationship between AF burden (AFB) and death among patients with cardiac implanted electronic devices is unknown. We sought to characterize the timing and progression of AFB before death.METHODS AND RESULTS: Using Merlin.netTM remote monitoring (RM) data, we analysed weekly AFB in patients age ≥55 years implanted with dual-chamber pacemaker, implantable cardioverter-defibrillator, or cardiac resynchronization therapy devices whose death was verified in the Social Security Death Index and who had continuous RM from 1year to 4weeks preceding death. Atrial fibrillation burden was defined as amount of time per week atrial rate exceeded a set threshold of 180 b.p.m. Case-crossover analysis was used to compare the AFB at every week to 6 control weeks at the start of the year before death. There were 3131 patients meeting analysis criteria (age at death 76±8years, 70% men). Weekly increase in AFB >6h was associated with increased odds of death, which was greatest at 4 weeks before death [odds ratio (OR) 2.30, 95% confidence interval (CI) 2.09-2.53; P<0.001]. Atrial fibrillation progression week-to-week >24h was associated with the greatest odds of death (OR 12.95, 95% 8.72-19.22; P<0.001). A combination of AFB >6h per week and activity <0.5h per day was associated with an increased odds of death.CONCLUSION: In this large patient cohort, AFB progression accelerated in the weeks leading to death. Continuous monitoring of AFB may help identify device patients who may be at risk for adverse outcomes, including death.

    View details for DOI 10.1093/europace/euy222

    View details for PubMedID 30462208

  • Venous access-site closure with vascular closure device vs. manual compression in patients undergoing catheter ablation or left atrial appendage occlusion under uninterrupted anticoagulation: a multicentre experience on efficacy and complications. Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology Mohanty, S., Trivedi, C., Beheiry, S., Al-Ahmad, A., Horton, R., Della Rocca, D. G., Gianni, C., Gasperetti, A., Abdul-Moheeth, M., Turakhia, M., Natale, A. 2019

    Abstract

    Aims: Manual compression (MC), widely used to achieve venous access haemostasis, needs prolonged immobilization and extended time-to-haemostasis. Vascular closure devices (VCD) have been reported to have significantly shorter time to haemostasis and ambulation in arterial access-site management. The current study aimed to evaluate the safety and efficacy as well as rate of urinary tract complications in patients receiving MC vs. VCD for venous access-site closure.Methods and results: A total of 803 consecutive patients undergoing catheter ablation or left atrial appendage closure were classified into the VCD (n=304) and the MC (n=499) group, based on the methods used for haemostasis at the venous access site. Foley catheter was used for bladder-emptying in all MC cases and 15 VCD patients. At one site, VCD group patients with experience of MC in prior ablations were asked to describe their overall satisfaction level after comparing the past experience with the present. Haemostasis was achieved effectively in both populations. No VCD cases required >2h bed rest, whereas 7 (1.4%) patients in the MC group needed prolonged immobilization (P=0.04). Significantly higher incidence of access-site haematoma (P=0.004) and urinary complications (P<0.05) were observed in the MC group. Majority of VCD patients (68%) with prior experience of MC for haemostasis expressed satisfaction over the early ambulation and ability to void urine without bladder catheterization.Conclusion: Vascular closure devices provided effective haemostasis, while reducing the access-site complications, ambulation time, and urinary complications.

    View details for DOI 10.1093/europace/euz004

    View details for PubMedID 30726903

  • Real-World Comparison of ClassesICandIII Antiarrhythmic Drugs asan Initial Rhythm Control Strategy inNewly Diagnosed Atrial Fibrillation: From the TREAT-AF Study. JACC. Clinical electrophysiology Kipp, R., Askari, M., Fan, J., Field, M. E., Turakhia, M. P. 2019; 5 (2): 231–41

    Abstract

    OBJECTIVES: In this study the authors investigated effectiveness and safety of an initial treatment strategy with classIC or class III antiarrhythmic drugs (AAD) for newly diagnosed atrial fibrillation (AF) or atrial flutter (AFL).BACKGROUND: There is limited evidence to guide optimal AAD selection for rhythm control in newly diagnosed AF/AFL.METHODS: Using data from TREAT-AF (The Retrospective Evaluation and Assessment of Therapies in AF), the authors performed a retrospective cohort study of patients with AF/AFL from 2004 to 2014 and class IC or class III AAD prescription within 90 days following diagnosis. Patients with prior myocardial infarction, heart failure, or end-stage renal disease were excluded. Inverse probability treatment weighted propensity scores were used to evaluate the association of AAD class on hospitalization and cardiovascular events. To evaluate residual confounding, falsification outcomes were evaluated.RESULTS: A total of 230,762 patients developed newly diagnosed AF/AFL during the study period. Of those, 3,973 patients (1.7%) were prescribed class IC and 6,909 (3.0%) were prescribed class III AAD. Median follow-up was 4.9 years. After inverse probability treatment weighted adjustment, class IC medications were associated with lower risk of hospitalizations for AF/AFL (hazard ratio [HR]: 0.77; 95% confidence interval [CI]: 0.73 to 0.81), cardiovascular disease (HR: 0.78; 95% CI: 0.75 to 0.81), heart failure (HR: 0.70; 95% CI: 0.64 to 0.76), and lower incidence of ischemic stroke (HR:0.74; 95% CI: 0.65 to 0.85). Similar results were found in CHADS2 (Congestive Heart Failure, Hypertension, Age≥75 Years, Diabetes Mellitus, Prior Stroke, Transient Ischemic Attack, or Thromboembolism) 0 or 1 and CHA2DS2-VASc (Congestive Heart Failure, Hypertension, Age≥75 Years, Diabetes Mellitus, Prior Stroke, Transient Ischemic Attack, or Thromboembolism, Vascular Disease, Age 65 to 74 Years, Sex) 0 or 1 subgroups. Falsification analyses for outcomes of urinary tract infection, pneumonia, and hip fracture were generally nonsignificant.CONCLUSIONS: Prescription of class IC AAD as initial treatment for newly diagnosed AF/AFL, compared with prescription of class III AAD, may be associated with lower risk of hospitalization and cardiovascular events.

    View details for DOI 10.1016/j.jacep.2018.08.025

    View details for PubMedID 30784696

  • Adherence to Guideline-Directed Stroke Prevention Therapy for Atrial Fibrillation is Achievable: First Results from Get With The Guidelines-Atrial Fibrillation (GWTG-AFIB). Circulation Piccini, J. P., Xu, H., Cox, M., Matsouaka, R. A., Fonarow, G. C., Butler, J., Curtis, A. B., Desai, N., Fang, M., McCabe, P. J., Page, R. L., Turakhia, M., Russo, A. M., Knight, B. P., Sidhu, M., Hurwitz, J. L., Ellenbogen, K. A., Lewis, W. R., Get With The Guidelines-AFIB Clinical Working Group and Hospitals 2019

    Abstract

    BACKGROUND: Efforts to improve oral anticoagulation (OAC) prescription in patients with atrial fibrillation (AF) have had limited success in improving guideline adherence.METHODS: We evaluated adherence to the ACC/AHA performance measures for OAC in eligible patients with a CHA2DS2-VASc≥2 and trends in prescription over time in the American Heart Association's Get With The Guidelines (GWTG) AFIB registry. Adjusted associations with in-hospital outcomes were also determined. The cohort included 33,235 AF admissions with a CHA2DS2-VASc≥2 enrolled at 115 sites between January 1, 2013 and September 31, 2017.RESULTS: The median age was 73 (65, 81), 52% were female, and the median CHA2DS2-VASc score was 4 (3, 5). At admission 16,206 (59.5%) with a prior diagnosis of AF were on OAC and OAC at admission was associated with a lower adjusted odds of in-hospital ischemic stroke (OR 0.38, 95% CI 0.24-0.59, p<0.0001). At discharge, prescription of OAC in eligible patients (no contraindications) was 93.5% (n=25,499/27,270). In a sensitivity analysis, when excluding only strict contraindications (4.6%, n=1,497/32,806), OAC prescription at discharge was 80.3%. Frequency of OAC was higher in those age ≤75, men, those with heart failure, prior AF ablation, and rhythm control (p<0.0001 for all). OAC use was lowest in Hispanic patients (90.2%, p<0.0001). Prescription of OAC at discharge in eligible patients improved over time from 79.9% to 96.6% (p<0.0001).CONCLUSIONS: Among hospitals participating in the GWTG-AFIB quality improvement program, OAC prescription at discharge in eligible guideline-indicated patients increased significantly and improved consistently over time. These data confirm that high-level adherence to guideline recommended stroke prevention is achievable.

    View details for DOI 10.1161/CIRCULATIONAHA.118.035909

    View details for PubMedID 30700141

  • Venous Vascular Closure System (VVCS) vs. Manual Compression (MC) for EP Catheter Ablation: The AMBULATE Randomized Trial Natale, A., Al-Ahmad, A., Bailey, S., Bunch, T., Compton, S., De Lurgio, D. B., Horton, R. P., Mittal, S., O'Neill, P., Spear, W., Turakhia, M. P. LIPPINCOTT WILLIAMS & WILKINS. 2018: E769
  • Assessment of Procedural Technique and Safety of Atrial Fibrillation Ablation: Data from the AHA/HRS Get With The Guidelines Atrial Fibrillation Registry Piccini, J. P., Liang, L., Matsouaka, R., Curtis, A. B., Day, J. D., Desai, N., Ellenbogen, K., Fang, M., Feld, G., Fonarow, G. C., Frankel, D. S., Hurwitz, J. L., Knight, B. P., Joglar, J., McCabe, P. J., Page, R. L., Russo, A. M., Sheth, K. N., Sidhu, M. S., Turakhia, M., Lewis, W. R. LIPPINCOTT WILLIAMS & WILKINS. 2018: E775
  • Antithrombotic Therapy for Atrial Fibrillation CHEST Guideline and Expert Panel Report CHEST Lip, G. H., Banerjee, A., Boriani, G., Chiang, C., Fargo, R., Freedman, B., Lane, D. A., Ruff, C. T., Turakhia, M., Werring, D., Patel, S., Moores, L. 2018; 154 (5): 1121–1201

    Abstract

    The risk of stroke is heterogeneous across different groups of patients with atrial fibrillation (AF), being dependent on the presence of various stroke risk factors. We provide recommendations for antithrombotic treatment based on net clinical benefit for patients with AF at varying levels of stroke risk and in a number of common clinical scenarios.Systematic literature reviews were conducted to identify relevant articles published from the last formal search perfomed for the Antithrombotic and Thrombolytic Therapy: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (9th Edition). The overall quality of the evidence was assessed using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach. Graded recommendations and ungraded consensus-based statements were drafted, voted on, and revised until consensus was reached.For patients with AF without valvular heart disease, including those with paroxysmal AF, who are at low risk of stroke (eg, CHA2DS2-VASc [congestive heart failure, hypertension, age ≥ 75 (doubled), diabetes, stroke (doubled)-vascular disease, age 65-74 and sex category (female)] score of 0 in males or 1 in females), we suggest no antithrombotic therapy. The next step is to consider stroke prevention (ie, oral anticoagulation therapy) for patients with 1 or more non-sex CHA2DS2-VASc stroke risk factors. For patients with a single non-sex CHA2DS2-VASc stroke risk factor, we suggest oral anticoagulation rather than no therapy, aspirin, or combination therapy with aspirin and clopidogrel; and for those at high risk of stroke (eg, CHA2DS2-VASc ≥ 2 in males or ≥ 3 in females), we recommend oral anticoagulation rather than no therapy, aspirin, or combination therapy with aspirin and clopidogrel. Where we recommend or suggest in favor of oral anticoagulation, we suggest using a non-vitamin K antagonist oral anticoagulant drug rather than adjusted-dose vitamin K antagonist therapy. With the latter, it is important to aim for good quality anticoagulation control with a time in therapeutic range > 70%. Attention to modifiable bleeding risk factors (eg, uncontrolled BP, labile international normalized ratios, concomitant use of aspirin or nonsteroidal antiinflammatory drugs in an anticoagulated patient, alcohol excess) should be made at each patient contact, and HAS-BLED (hypertension, abnormal renal/liver function [1 point each], stroke, bleeding history or predisposition, labile international normalized ratio, elderly (0.65), drugs/alcohol concomitantly [1 point each]) score used to assess the risk of bleeding where high risk patients (≥ 3) should be reviewed and followed up more frequently.Oral anticoagulation is the optimal choice of antithrombotic therapy for patients with AF with ≥1 non-sex CHA2DS2-VASc stroke risk factor(s).

    View details for DOI 10.1016/j.chest.2018.07.040

    View details for Web of Science ID 000449273000027

    View details for PubMedID 30144419

  • Rationale and design of a large-scale, app-based study to identify cardiac arrhythmias using a smartwatch: The Apple Heart Study. American heart journal Turakhia, M. P., Desai, M., Hedlin, H., Rajmane, A., Talati, N., Ferris, T., Desai, S., Nag, D., Patel, M., Kowey, P., Rumsfeld, J. S., Russo, A. M., Hills, M. T., Granger, C. B., Mahaffey, K. W., Perez, M. V. 2018

    Abstract

    BACKGROUND: Smartwatch and fitness band wearable consumer electronics can passively measure pulse rate from the wrist using photoplethysmography (PPG). Identification of pulse irregularity or variability from these data has the potential to identify atrial fibrillation or atrial flutter (AF, collectively). The rapidly expanding consumer base of these devices allows for detection of undiagnosed AF at scale.METHODS: The Apple Heart Study is a prospective, single arm pragmatic study that has enrolled 419,093 participants (NCT03335800). The primary objective is to measure the proportion of participants with an irregular pulse detected by the Apple Watch (Apple Inc, Cupertino, CA) with AF on subsequent ambulatory ECG patch monitoring. The secondary objectives are to: 1) characterize the concordance of pulse irregularity notification episodes from the Apple Watch with simultaneously recorded ambulatory ECGs; 2) estimate the rate of initial contact with a health care provider within 3 months after notification of pulse irregularity. The study is conducted virtually, with screening, consent and data collection performed electronically from within an accompanying smartphone app. Study visits are performed by telehealth study physicians via video chat through the app, and ambulatory ECG patches are mailed to the participants.CONCLUSIONS: The results of this trial will provide initial evidence for the ability of a smartwatch algorithm to identify pulse irregularity and variability which may reflect previously unknown AF. The Apple Heart Study will help provide a foundation for how wearable technology can inform the clinical approach to AF identification and screening.

    View details for DOI 10.1016/j.ahj.2018.09.002

    View details for PubMedID 30392584

  • Moving From Big Data to Deep Learning-The Case of Atrial Fibrillation JAMA CARDIOLOGY Turakhia, M. P. 2018; 3 (5): 371–72

    View details for DOI 10.1001/jamacardio.2018.0207

    View details for Web of Science ID 000432389900005

    View details for PubMedID 29562077

  • Estimated prevalence of undiagnosed atrial fibrillation in the United States PLOS ONE Turakhia, M. P., Shafrin, J., Bognar, K., Trocio, J., Abdulsattar, Y., Wiederkehr, D., Goldman, D. P. 2018; 13 (4): e0195088

    Abstract

    As atrial fibrillation (AF) is often asymptomatic, it may remain undiagnosed until or even after development of complications, such as stroke. Consequently the observed prevalence of AF may underestimate total disease burden.To estimate the prevalence of undiagnosed AF in the United States, we performed a retrospective cohort modeling study in working age (18-64) and elderly (≥65) people using commercial and Medicare administrative claims databases. We identified patients in years 2004-2010 with incident AF following an ischemic stroke. Using a back-calculation methodology, we estimated the prevalence of undiagnosed AF as the ratio of the number of post-stroke AF patients and the CHADS2-specific stroke probability for each patient, adjusting for age and gender composition based on United States census data.The estimated prevalence of AF (diagnosed and undiagnosed) was 3,873,900 (95%CI: 3,675,200-4,702,600) elderly and 1,457,100 (95%CI: 1,218,500-1,695,800) working age adults, representing 10.0% and 0.92% of the respective populations. Of these, 698,900 were undiagnosed: 535,400 (95%CI: 331,900-804,400) elderly and 163,500 (95%CI: 17,700-400,000) working age adults, representing 1.3% and 0.09% of the respective populations. Among all undiagnosed cases, 77% had a CHADS2 score ≥1, and 56% had CHADS2 score ≥2.Using a back-calculation approach, we estimate that the total AF prevalence in 2009 was 5.3 million of which 0.7 million (13.1% of AF cases) were undiagnosed. Over half of the modeled population with undiagnosed AF was at moderate to high risk of stroke.

    View details for DOI 10.1371/journal.pone.0195088

    View details for Web of Science ID 000429791900022

    View details for PubMedID 29649277

    View details for PubMedCentralID PMC5896911

  • A review of the impact of vascular closure devices and patient preferences in cardiac ablation Huber, C., Thanh Thanh, May-Slater, S., Ballotta, J., Turakhia, M. WILEY. 2018: 676–77
  • Digoxin in Atrial Fibrillation? Leave it Out of the Medicine Cabinet JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Turakhia, M. P. 2018; 71 (10): 1075–77

    View details for DOI 10.1016/j.jacc.2018.01.015

    View details for Web of Science ID 000426569700002

    View details for PubMedID 29519346

  • ALTERNATIVE METRICS BY SYSTEMATIC REVIEW INCLUSION STATUS OF STUDIES OF CATHETER ABLATION FOR ATRIAL FIBRILLATION: FINDINGS FROM THE SMASH-AF META-ANALYSIS STUDY COHORT Yunus, F., Leef, G., Cluckey, A., Askari, M., Turakhia, M., Perino, A. ELSEVIER SCIENCE INC. 2018: 342
  • Patient and facility variation in costs of catheter ablation for atrial fibrillation. Journal of cardiovascular electrophysiology Perino, A. C., Fan, J., Schmitt, S., Kaiser, D. W., Heidenreich, P. A., Narayan, S. M., Wang, P. J., Chang, A. Y., Turakhia, M. P. 2018

    Abstract

    Cost-effectiveness or value of cardiovascular therapies may be undermined by unwarranted cost variation, particularly for heterogeneous procedures such as catheter ablation for atrial fibrillation (AF). We sought to characterize cost variation of AF ablation in the U.S. health care system and the relationship between cost and outcomes.We performed a retrospective cohort study using data from the MarketScan® commercial claims and Medicare supplemental databases including patients who received an AF ablation from 2007 through 2011. We aggregated encounter cost, reflecting total payments received for the encounter, to the facility level to calculate median facility cost. We classified procedures as outpatient or inpatient and assessed for association between cost and 30-day and one-year outcomes. The analysis cohort included 9,415 AF ablations (59±11 years; 28% female; 52% outpatient) occurring at 327 facilities, with large cost variation across facilities (median: $25,100; 25th percentile: $18,900, 75th percentile: $35,600, 95th percentile: $57,800). Among outpatient procedures, there was reduced health care utilization in higher cost quintiles with reductions in rehospitalization at 30-days (Quintile 1: 16.1%, Quintile 5: 8.8%, p < 0.001) and one-year (Quintile 1: 34.8%, Quintile 5: 25.6%, p < 0.001), which remained significant in multivariate analysis.Although median costs of AF ablation are below amounts used in prior cost-effectiveness studies that demonstrated good value, large facility variation in cost suggests opportunities for cost reduction. However, for outpatient encounters, association of cost to modestly improved outcomes suggests cost containment strategies could have variable effects. This article is protected by copyright. All rights reserved.

    View details for DOI 10.1111/jce.13655

    View details for PubMedID 29864193

  • Association of Healthcare Plan with Atrial Fibrillation Prescription Patterns. Clinical cardiology Chang, A. Y., Askari, M., Fan, J., Heidenreich, P. A., Ho, P. M., Mahaffey, K. W., Ullal, A. J., Perino, A. C., Turakhia, M. P. 2018

    Abstract

    Atrial fibrillation (AF) is treated by many types of physician specialists, including primary care physicians (PCPs). Health plans have different policies for how patients encounter these providers, and these may affect selection of AF treatment strategy.We hypothesized that healthcare plans with PCP-gatekeeping to specialist access may be associated with different pharmacologic treatments for AF.We performed a retrospective cohort study using a commercial pharmaceutical claims database. We utilized logistic regression models to compare odds of prescription of oral anticoagulant (OAC), non-vitamin K-dependent oral anticoagulant (NOAC), rate control, and rhythm control medications used to treat AF between patients with PCP-gated healthcare plans (e.g. HMO, EPO, POS) and patients with non-PCP-gated healthcare plans (e.g. PPO, CHDP, HDHP, Comprehensive) between 2007 and 2012. We also calculated median time to receipt of therapy within 90 days of index AF diagnosis.We found similar odds of OAC prescription at 90 days following new AF diagnosis in patients with PCP-gated plans compared to those with non-PCP-gated plans (OR: OAC 1.01, p=0.84; warfarin 1.05, p=0.08). Relative odds were similar for rate control (1.17, p<0.01) and rhythm control agents (0.93, p=0.03). However, PCP-gated plan patients had slightly lower likelihood of being prescribed NOACs (0.82, p=0.001) than non-gated plan patients. Elapsed time until receipt of medication was similar between PCP-gated and non-gated groups across drug classes.Pharmaceutical claims data do not suggest that PCP-gatekeeping by healthcare plans is a structural barrier to AF therapy, although it was associated with lower use of NOACs.

    View details for DOI 10.1002/clc.23042

    View details for PubMedID 30098034

  • Pharmacokinetics of Tecarfarin and Warfarin in Patients with Severe Chronic Kidney Disease THROMBOSIS AND HAEMOSTASIS Albrecht, D., Turakhia, M. P., Ries, D., Marbury, T., Smith, W., Dillon, D., Milner, P. G., Midei, M. G. 2017; 117 (11): 2026–33

    Abstract

    Chronic kidney disease (CKD) complicates warfarin anticoagulation partially through its effect on CYP2C9 activity. Tecarfarin, a novel vitamin K antagonist, is not metabolized by CYP2C9. To evaluate the effect of CKD on their metabolism, we measured PK parameters of warfarin and tecarfarin in subjects with and without CKD. CKD subjects with estimated glomerular filtration rate < 30 mL/min not on dialysis (n = 13) were matched to healthy volunteers (HVs) (n = 10). Each subject was randomized to either warfarin 10 mg or tecarfarin 30 mg and was later crossed over to the other drug. PK parameters were measured following each drug. Mean plasma concentrations of (S)-warfarin and (R,S)-warfarin were higher (44 and 27%, respectively) in the subjects with CKD than in the healthy subjects. Both of these values fell outside of the 90% confidence interval of equivalence. For tecarfarin, the difference was less than 15% higher. Elimination half-life (t1/2) increased by 20% for (S)-warfarin and by 8% for (R,S)-warfarin and decreased by 8% for tecarfarin. The mean plasma concentration for tecarfarin's inactive metabolite ATI-5900 increased by approximately eightfold. CKD increased the effect of CYP2C9 genetic variation on (S)-warfarin and (R,S)-warfarin metabolism. Tecarfarin exposure was similar between the HVs and the CKD subjects regardless of CYP2C9 genotype. There were neither serious adverse events (SAEs) nor treatment-emergent adverse events (TEAEs) for any subject in the study. CKD inhibits metabolism of (S)-warfarin and (R,S)-warfarin, but not tecarfarin. The safety of repeated dosing of tecarfarin in CKD patients remains unknown. However, if the PK findings of this single-dose study are present with repeated dosing, tecarfarin may lead to dosing that is more predictable than warfarin in CKD patients who require anticoagulation therapy.

    View details for DOI 10.1160/TH16-10-0815

    View details for Web of Science ID 000415913400004

    View details for PubMedID 28933798

  • Towards a Mechanistic Understanding and Treatment of a Progressive Disease: Atrial Fibrillation. Journal of atrial fibrillation Yang, F., Tiano, J., Mittal, S., Turakhia, M., Jacobowitz, I., Greenberg, Y. 2017; 10 (3): 1627

    Abstract

    Atrial fibrosis appears to be a key factor in the genesis and/or perpetuation of atrial fibrillation (AF). The pathological distribution of atrial fibrosis is geographically consistent with the attachments between the posterior left atrium and the pericardium along the reflections where wall stiffness is increased and structural changes are found. While there is a wide range of complex etiological factors and electrophysiological mechanisms in AF, there is evidence for a common pathophysiological pathway that could account for deliberate substrate formation and progression of AF. Anatomical stresses along the atrium, mediated by the elastic modulus mismatch between atrial tissue and the pericardium, result in inflammatory and fibrotic changes which create the substrate for atrial fibrillation. This may explain the anatomical predominance of pulmonary vein triggers earlier in the development of atrial fibrillation and the increasing involvement of the atrium as the disease progresses. Ablative treatments that address the progressive nature of atrial fibrillation and fibrosis may yield improved success rates.

    View details for DOI 10.4022/jafib.1627

    View details for PubMedID 29250240

  • Screening for atrial fibrillation: a European Heart Rhythm Association (EHRA) consensus document endorsed by the Heart Rhythm Society (HRS), Asia Pacific Heart Rhythm Society (APHRS), and Sociedad Latinoamericana de Estimulaci<remove>n Cardiaca y Electrofisiologia (SOLAECE) EUROPACE Mairesse, G. H., Moran, P., Van Gelder, I. C., Elsner, C., Rosenqvist, M., Mant, J., Banerjee, A., Gorenek, B., Brachmann, J., Varma, N., de Lima, G., Kalman, J., Claes, N., Lobban, T., Lane, D., Lip, G. H., Boriani, G., Fauchier, L., Jung, W., Savelieva, I., Freedman, B., Chen, S., Isa, R., Turakhia, M., Sapp, J. 2017; 19 (10): 1589–1623

    View details for DOI 10.1093/europace/eux177

    View details for Web of Science ID 000412840300001

    View details for PubMedID 29048522

  • Adherence and outcomes to direct oral anticoagulants among patients with atrial fibrillation: findings from the veterans health administration BMC CARDIOVASCULAR DISORDERS Borne, R. T., O'Donnell, C., Turakhia, M. P., Varosy, P. D., Jackevicius, C. A., Marzec, L. N., Masoudi, F. A., Hess, P. L., Maddox, T. M., Ho, P. 2017; 17: 236

    Abstract

    The direct oral anticoagulants (DOACs) reduce the risk of stroke in moderate to high-risk patients with non-valvular atrial fibrillation (AF). Yet, concerns remain regarding its routine use in real world practice. We sought to describe adherence patterns and the association between adherence and outcomes to the DOACs among outpatients with AF.We performed a retrospective cohort study of patients in the VA Healthcare System who initiated pharmacotherapy with dabigatran, rivaroxaban, or apixaban between November 2010 and January 2015 for non-valvular AF with CHA2DS2-VASc score ≥ 2. Adherence was determined using pharmacy refill data and estimated by the proportion of days covered (PDC) over the first year of therapy. Clinical outcomes, including all-cause mortality and stroke, were measured at 6 months and used to assess measures of adherence for each DOAC.A total of 2882 patients were included. Most were prescribed dabigatran (72.7%), compared with rivaroxaban (19.8%) or apixaban (7.5%). The mean PDC was 0.84 ± 0.20 for dabigatran, 0.86 ± 0.18 for rivaroxaban, and 0.89 ± 0.14 for apixaban (p < 0.01). The proportion of non-adherent patients, PDC <0.80, was 27.6% for all and varied according DOAC. Lower adherence to dabigatran was associated with higher risk of mortality and stroke (HR 1.07; 1.03-1.12 per 0.10 decline in PDC).In a real-world VA population being prescribed anticoagulation for AF, more than one quarter had sub-optimal adherence. Lower adherence was associated with a higher risk of mortality and stroke. Efforts identifying non-adherent patients, and targeted adherence interventions are needed to improve outcomes.

    View details for DOI 10.1186/s12872-017-0671-6

    View details for Web of Science ID 000409138600002

    View details for PubMedID 28865440

    View details for PubMedCentralID PMC5581418

  • Telemedicine for Management of Implantable Defibrillators Lessons Learned and a Look Toward the Future CIRCULATION-ARRHYTHMIA AND ELECTROPHYSIOLOGY Turakhia, M. P. 2017; 10 (9)
  • Early non-persistence with dabigatran and rivaroxaban in patients with atrial fibrillation HEART Jackevicius, C. A., Tsadok, M., Essebag, V., Atzema, C., Eisenberg, M. J., Tu, J. V., Lu, L., Rahme, E., Ho, P., Turakhia, M., Humphries, K. H., Behlouli, H., Zhou, L., Pilote, L. 2017; 103 (17): 1331–38

    Abstract

    Dabigatran and rivaroxaban are novel oral anticoagulants (NOACs) approved for stroke prevention in atrial fibrillation (AF). Although NOACs are more convenient than warfarin, their lack of monitoring may predispose patients to non-persistence. Limited information is available on NOAC non-persistence rates and related clinical outcomes in clinical practice.We conducted a retrospective cohort study using administrative data from Ontario, Canada, from January 1998 to March 2014 of patients with AF who were dispensed dabigatran or rivaroxaban. Non-persistence was defined as a gap in dabigatran or rivaroxaban prescriptions ≥14 days. A multivariable Cox proportional hazards model was used to estimate the primary composite outcome of stroke, transient ischaemic attack (TIA) and mortality associated with non-persistence.The cohort consisted of 15 857 dabigatran (age 80.7±6.7 year) and 10 119 rivaroxaban users (age 77.0±7.1 year) with women comprising 52% of each medication group. At 6 months, 36.4% of patients were non-persistent to dabigatran, while 31.9% of patients were non-persistent to rivaroxaban. Stroke/TIA/death was significantly higher for those non-persistent to dabigatran (HR 1.76 (95% CI 1.60 to 1.94); p<0.0001) or rivaroxaban (HR 1.89 (95% CI 1.64 to 2.19); p<0.0001) compared with those who were persistent. Risk of stroke/TIA was markedly higher in non-persistent patients to dabigatran (HR 3.75 (95% CI 2.59 to 5.43); p<0.0001) and rivaroxaban (HR 6.25 (95% CI 3.37 to 11.58); p<0.0001) than those persistent.NOAC non-persistence rates are high in clinical practice, with approximately one in three patients becoming non-persistent to dabigatran or rivaroxaban within 6 months after drug initiation. Non-persistence with either dabigatran or rivaroxaban is significantly associated with worse clinical outcomes of stroke/TIA/death.

    View details for DOI 10.1136/heartjnl-2016-310672

    View details for Web of Science ID 000407613900007

    View details for PubMedID 28286333

  • Risk and Consequences of Atrial Fibrillation It's in the Jeans, Not the Genes JAMA CARDIOLOGY Turakhia, M. P. 2017; 2 (8): 871

    View details for DOI 10.1001/jamacardio.2017.1856

    View details for Web of Science ID 000407806100008

    View details for PubMedID 28678982

  • Response by Vaidya et al to Letter Regarding Article, "Burden of Arrhythmia in Pregnancy" CIRCULATION Vaidya, V. R., Arora, S., Patel, N., Badheka, A., Patel, N., Agnihotri, K., Billimoria, Z., Turakhia, M. P., Friedman, P. A., Madhavan, M., Kapa, S., Noseworthy, P. A., Cha, Y., Gersh, B., Asirvatham, S. J., Deshmukh, A. J. 2017; 136 (2): 244–45
  • Treating Specialty and Outcomes in Newly Diagnosed Atrial Fibrillation From the TREAT-AF Study JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Perino, A. C., Fan, J., Schmitt, S. K., Askari, M., Kaiser, D. W., Deshmukh, A., Heidenreich, P. A., Swan, C., Narayan, S. M., Wang, P. J., Turakhia, M. P. 2017; 70 (1): 78–86

    Abstract

    Atrial fibrillation (AF) occurs in many clinical contexts and is diagnosed and treated by clinicians across many specialties. This approach has resulted in treatment variations.The goal of this study was to evaluate the association between treating specialty and AF outcomes among patients newly diagnosed with AF.Using data from the TREAT-AF (Retrospective Evaluation and Assessment of Therapies in AF) study from the Veterans Health Administration, patients with newly diagnosed, nonvalvular AF between 2004 and 2012 were identified who had at least 1 outpatient encounter with primary care or cardiology within 90 days of the AF diagnosis. Cox proportional hazards regression was used to evaluate the association between treating specialty and AF outcomes.Among 184,161 patients with newly diagnosed AF (age 70 ± 11 years; 1.7% women; CHA2DS2-VASc score 2.6 ± 1.7), 40% received cardiology care and 60% received primary care only. After adjustment for covariates, cardiology care was associated with reductions in stroke (hazard ratio [HR]: 0.91; 95% confidence interval [CI]: 0.86 to 0.96; p < 0.001) and death (HR: 0.89; 95% CI: 0.88 to 0.91; p < 0.0001) and increases in hospitalizations for AF/supraventricular tachycardia (HR: 1.38; 95% CI: 1.35 to 1.42; p < 0.0001) and myocardial infarction (HR: 1.03; 95% CI: 1.00 to 1.05; p < 0.04). The propensity-matched cohort had similar results. In mediation analysis, oral anticoagulation prescription within 90 days of diagnosis may have mediated reductions in stroke but did not mediate reductions in survival.In patients with newly diagnosed AF, cardiology care was associated with improved outcomes, potentially mediated by early prescription of oral anticoagulation therapy. Although hypothesis-generating, these data warrant serious consideration and study of health care system interventions at the time of new AF diagnosis.

    View details for DOI 10.1016/j.jacc.2017.04.054

    View details for Web of Science ID 000404045700008

    View details for PubMedID 28662810

    View details for PubMedCentralID PMC5830104

  • Warfarin utilisation and anticoagulation control in patients with atrial fibrillation and chronic kidney disease HEART Yang, F., Hellyer, J. A., Than, C., Ullal, A. J., Kaiser, D. W., Heidenreich, P. A., Hoang, D. D., Winkelmayer, W. C., Schmitt, S., Frayne, S. M., Phibbs, C. S., Turakhia, M. P. 2017; 103 (11): 818-826

    Abstract

    To evaluate warfarin prescription, quality of international normalised ratio (INR) monitoring and of INR control in patients with atrial fibrillation (AF) and chronic kidney disease (CKD).We performed a retrospective cohort study of patients with newly diagnosed AF in the Veterans Administration (VA) healthcare system. We evaluated anticoagulation prescription, INR monitoring intensity and time in and outside INR therapeutic range (TTR) stratified by CKD.Of 123 188 patients with newly diagnosed AF, use of warfarin decreased with increasing severity of CKD (57.2%-46.4%), although it was higher among patients on dialysis (62.3%). Although INR monitoring intensity was similar across CKD strata, the proportion with TTR≥60% decreased with CKD severity, with only 21% of patients on dialysis achieving TTR≥60%. After multivariate adjustment, the magnitude of TTR reduction increased with CKD severity. Patients on dialysis had the highest time markedly out of range with INR <1.5 or >3.5 (30%); 12% of INR time was >3.5, and low TTR persisted for up to 3 years.There is a wide variation in anticoagulation prescription based on CKD severity. Patients with moderate-to-severe CKD, including dialysis, have substantially reduced TTR, despite comparable INR monitoring intensity. These findings have implications for more intensive warfarin management strategies in CKD or alternative therapies such as direct oral anticoagulants.

    View details for DOI 10.1136/heartjnl-2016-309266

    View details for Web of Science ID 000401028400006

  • Screening for Atrial Fibrillation A Report of the AF-SCREEN International Collaboration CIRCULATION Freedman, B., Camm, J., Calkins, H., Healey, J. S., Rosenqvist, M., Wang, J., Albert, C. M., Anderson, C. S., Antoniou, S., Benjamin, E. J., Boriani, G., Brachmann, H., Brachmann, J., Brandes, A., Chao, T., Conen, D., Engdahl, J., Fauchier, L., Fitzmaurice, D. A., Friberg, L., Gersh, B. J., Gladstone, D. J., Glotzer, T. V., Gwynne, K., Hankey, G. J., Harbison, J., Hillis, G. S., Hills, M. T., Kamel, H., Kirchhof, P., Kowey, P. R., Krieger, D., Lee, V. W., Levin, L., Lip, G. Y., Lobban, T., Lowres, N., Mairesse, G. H., Martinez, C., Neubeck, L., Orchard, J., Piccini, J. P., Poppe, K., Potpara, T. S., Puererfellner, H., Rienstra, M., Sandhu, R. K., Schnabel, R. B., Siu, C., Steinhubl, S., Svendsen, J. H., Svennberg, E., Themistoclakis, S., Tieleman, R. G., Turakhia, M. P., Tveit, A., Uittenbogaart, S. B., van Gelder, I. C., Verma, A., Wachter, R., Yan, B. P. 2017; 135 (19): 1851-?

    Abstract

    Approximately 10% of ischemic strokes are associated with atrial fibrillation (AF) first diagnosed at the time of stroke. Detecting asymptomatic AF would provide an opportunity to prevent these strokes by instituting appropriate anticoagulation. The AF-SCREEN international collaboration was formed in September 2015 to promote discussion and research about AF screening as a strategy to reduce stroke and death and to provide advocacy for implementation of country-specific AF screening programs. During 2016, 60 expert members of AF-SCREEN, including physicians, nurses, allied health professionals, health economists, and patient advocates, were invited to prepare sections of a draft document. In August 2016, 51 members met in Rome to discuss the draft document and consider the key points arising from it using a Delphi process. These key points emphasize that screen-detected AF found at a single timepoint or by intermittent ECG recordings over 2 weeks is not a benign condition and, with additional stroke factors, carries sufficient risk of stroke to justify consideration of anticoagulation. With regard to the methods of mass screening, handheld ECG devices have the advantage of providing a verifiable ECG trace that guidelines require for AF diagnosis and would therefore be preferred as screening tools. Certain patient groups, such as those with recent embolic stroke of uncertain source (ESUS), require more intensive monitoring for AF. Settings for screening include various venues in both the community and the clinic, but they must be linked to a pathway for appropriate diagnosis and management for screening to be effective. It is recognized that health resources vary widely between countries and health systems, so the setting for AF screening should be both country- and health system-specific. Based on current knowledge, this white paper provides a strong case for AF screening now while recognizing that large randomized outcomes studies would be helpful to strengthen the evidence base.

    View details for DOI 10.1161/CIRCULATIONAHA.116.026693

    View details for Web of Science ID 000400757900017

    View details for PubMedID 28483832

  • Contemporary Trends in Oral Anticoagulant Prescription in Atrial Fibrillation Patients at Low to Moderate Risk of Stroke After Guideline-Recommended Change in Use of the CHADS(2) to the CHA(2)DS(2)-VASc Score for Thromboembolic Risk Assessment Analysis From the National Cardiovascular Data Registry's Outpatient Practice Innovation and Clinical Excellence Atrial Fibrillation Registry CIRCULATION-CARDIOVASCULAR QUALITY AND OUTCOMES Katz, D. F., Maddox, T. M., Turakhia, M., Gehi, A., O'Brien, E. C., Lubitz, S. A., Turchin, A., Doros, G., Lei, L., Varosy, P., Marzec, L., Hsu, J. C. 2017; 10 (5)
  • What Explains Atrial Fibrillation Mechanisms at Sites Where Ablation Terminates Persistent Atrial Fibrillation Prior to Pulmonary Vein Isolation? Navara, R., Meckler, G. L., Kowalewski, C. B., Shenasa, F., Baykaner, T., Zaman, U. B., Al-Husseini, M., Hossainy, S., Krummen, D., Brachmann, J., Viswanathan, M., Park, S., Turakhia, M., Wang, P. J., Narayan, S. M. WILEY. 2017: 607
  • Factors associated with rhythm control treatment decisions in patients with atrial fibrillation-Insights from the NCDR PINNACLE registry AMERICAN HEART JOURNAL Gehi, A. K., Doros, G., Glorioso, T. J., Grunwald, G. K., Hsu, J., Song, Y., Turakhia, M. P., Turchin, A., Virani, S. S., Maddox, T. M. 2017; 187: 88–97

    Abstract

    Decisions to use rhythm control in atrial fibrillation (AF) should generally be dictated by patient factors, such as quality of life, heart failure, and other comorbidities. Whether or not other factors affect decisions about the use of rhythm control, and catheter ablation in particular, is unknown.A cohort of all patients diagnosed with nonvalvular AF were identified from the National Cardiovascular Data Registry's Practice Innovation and Clinical Excellence (PINNACLE) AF registry of US outpatient cardiology practices during the study period from May 1, 2008, to December 31, 2014. Overall and practice-specific rates of rhythm control (cardioversion, antiarrhythmic drug therapy, or catheter ablation) were assessed. We assessed patient and practice factors associated with rhythm control and determined the relative contribution of patient, practice, and unmeasured practice factors with its use.Among 511,958 PINNACLE AF patients, 22.3% were treated with rhythm control and 2.9% underwent catheter ablation. Significant practice variation in rhythm control was present (median rate of rhythm control across practices 22.8%, range 0.2%-62.9%). Significant patient factors associated with rhythm control therapy included white (vs nonwhite) race (odds ratio [OR] 2.43, P<.001), private (vs nonprivate) insurance (OR 1.04, P<.001), and whether a patient was seen by an electrophysiologist (OR 1.77, P<.001). In an analysis of the relative contribution of patient, practice, and unmeasured practice factors with rhythm control, the contribution of unmeasured practice factors (95% range OR 0.29-3.44) exceeded that of either patient (95% range OR 0.46-2.30) or practice (95% range OR 0.15-2.77) factors.One in 5 AF patients in the PINNACLE registry received rhythm control, and 1 in 50 received catheter ablation, suggesting that rhythm control may be underused. A variety of measured and unmeasured practice factors unrelated to patient characteristics play a disproportionate role in the use of rhythm control treatment decisions. Understanding the drivers of these decisions may identify inappropriate treatment variation and better inform optimal use of these therapies.

    View details for DOI 10.1016/j.ahj.2017.02.006

    View details for Web of Science ID 000401053600011

    View details for PubMedID 28454812

  • Long-term electrocardiographic safety monitoring in clinical drug development: A report from the Cardiac Safety Research Consortium AMERICAN HEART JOURNAL Piccini, J. P., Clark, R. L., Kowey, P. R., Mittal, S., Dunnmon, P., Stockbridge, N., Reiffel, J. A., Turakhia, M. P., Ziegler, P. D., Kleiman, R. B., Ismat, F., Sager, P. 2017; 187: 156–69

    Abstract

    This white paper, prepared by members of the Cardiac Safety Research Consortium (CSRC), discusses important issues regarding scientific and clinical aspects of long-term electrocardiographic safety monitoring during clinical drug development. To promote multistakeholder discussion of this topic, a Cardiac Safety Research Consortium-sponsored Think Tank was held on 2 December 2015 at the American College of Cardiology's Heart House in Washington, DC. The goal of the Think Tank was to explore how and under what circumstances new and evolving ambulatory monitoring technologies could be used to improve and streamline drug development. This paper provides a detailed summary of discussions at the Think Tank: it does not represent regulatory guidance.

    View details for DOI 10.1016/j.ahj.2017.01.012

    View details for Web of Science ID 000401053600018

    View details for PubMedID 28454799

  • 2017 ISHNE-HRS expert consensus statement on ambulatory ECG and external cardiac monitoring/telemetry ANNALS OF NONINVASIVE ELECTROCARDIOLOGY Steinberg, J. S., Varma, N., Cygankiewicz, I., Aziz, P., Balsam, P., Baranchuk, A., Cantillon, D. J., Dilaveris, P., Dubner, S. J., El-Sherif, N., Krol, J., Kurpesa, M., La Rovere, M., Lobodzinski, S. S., Locati, E. T., Mittal, S., Olshansky, B., Piotrowicz, E., Saxon, L., Stone, P. H., Tereshchenko, L., Turitto, G., Wimmer, N. J., Verrier, R. L., Zareba, W., Piotrowicz, R. 2017; 22 (3)

    Abstract

    Ambulatory ECG (AECG) is very commonly employed in a variety of clinical contexts to detect cardiac arrhythmias and/or arrhythmia patterns which are not readily obtained from the standard ECG. Accurate and timely characterization of arrhythmias is crucial to direct therapies that can have an important impact on diagnosis, prognosis or patient symptom status. The rhythm information derived from the large variety of AECG recording systems can often lead to appropriate and patient-specific medical and interventional management. The details in this document provide background and framework from which to apply AECG techniques in clinical practice, as well as clinical research.

    View details for DOI 10.1111/anec.12447

    View details for Web of Science ID 000404596800001

    View details for PubMedID 28480632

  • SECULAR TRENDS IN REPORTED SUCCESS RATES OF CATHETER ABLATION FOR NON-PAROXYSMAL ATRIAL FIBRILLATION: FINDINGS FROM THE SMASH-AF META-ANALYSIS STUDY COHORT Leef, G., Cluckey, A., Yunus, F., Askari, M., Schuit, E., Heidenreich, P., Turakhia, M., Perino, A. ELSEVIER SCIENCE INC. 2017: 451
  • SUCCESS RATES BY ABLATION LESION SET OF CATHETER ABLATION FOR PAROXYSMAL ATRIAL FIBRILLATION: FINDINGS FROM THE SMASH-AF META-ANALYSIS STUDY COHORT Cluckey, A., Yunus, F., Leef, G., Askari, M., Schuit, E., Heidenreich, P., Turakhia, M., Perino, A. ELSEVIER SCIENCE INC. 2017: 370
  • INCLUSION OF WOMEN IN STUDIES OF CATHETER ABLATION FOR ATRIAL FIBRILLATION: FINDINGS FROM THE SMASH-AF META-ANALYSIS STUDY COHORT Yunus, F., Leef, G., Cluckey, A., Askari, M., Schuit, E., Heidenreich, P., Turakhia, M., Perino, A. ELSEVIER SCIENCE INC. 2017: 537
  • Burden of Arrhythmia in Pregnancy CIRCULATION Vaidya, V. R., Arora, S., Patel, N., Badheka, A. O., Patel, N., Agnihotri, K., Billimoria, Z., Turakhia, M. P., Friedman, P. A., Madhavan, M., Kapa, S., Noseworthy, P. A., Cha, Y., Gersh, B., Asirvatham, S. J., Deshmukh, A. J. 2017; 135 (6): 619–21
  • Healthcare Utilization and Expenditures Associated With Appropriate and Inappropriate Implantable Defibrillator Shocks CIRCULATION-CARDIOVASCULAR QUALITY AND OUTCOMES Turakhia, M. P., Zweibel, S., Swain, A. L., Mollenkopf, S. A., Reynolds, M. R. 2017; 10 (2)

    Abstract

    In patients with implantable cardioverter-defibrillators, healthcare utilization (HCU) and expenditures related to shocks have not been quantified.We performed a retrospective cohort study of patients with implantable cardioverter-defibrillators identified from commercial and Medicare supplemental claims databases linked to adjudicated shock events from remote monitoring data. A shock event was defined as ≥1 spontaneous shocks delivered by an implanted device. Shock-related HCU was ascertained from inpatient and outpatient claims within 7 days following a shock event. Shock events were adjudicated and classified as inappropriate or appropriate, and HCU and expenditures, stratified by shock type, were quantified. Of 10 266 linked patients, 963 (9.4%) patients (61.3±13.6 years; 81% male) had 1885 shock events (56% appropriate, 38% inappropriate, and 6% indeterminate). Of these events, 867 (46%) had shock-related HCU (14% inpatient and 32% outpatient). After shocks, inpatient cardiovascular procedures were common, including echocardiography (59%), electrophysiology study or ablation (34%), stress testing (16%), and lead revision (11%). Cardiac catheterization was common (71% and 51%), but percutaneous coronary intervention was low (6.5% and 5.0%) after appropriate and inappropriate shocks. Expenditures related to appropriate and inappropriate shocks were not significantly different.After implantable cardioverter-defibrillator shock, related HCU was common, with 1 in 3 shock events followed by outpatient HCU and 1 in 7 followed by hospitalization. Use of invasive cardiovascular procedures was substantial, even after inappropriate shocks, which comprised 38% of all shocks. Implantable cardioverter-defibrillator shocks seem to trigger a cascade of health care. Strategies to reduce shocks could result in cost savings.

    View details for DOI 10.1161/CIRCOUTCOMES.115.002210

    View details for Web of Science ID 000394569400002

    View details for PubMedID 28196927

  • Impact of Baseline Stroke Risk and Bleeding Risk on Warfarin International Normalized Ratio Control in Atrial Fibrillation (from the TREAT-AF Study) AMERICAN JOURNAL OF CARDIOLOGY Hellyer, J. A., Azarbal, F., Than, C. T., Fan, J., Schmitt, S. K., Yang, F., Frayne, S. M., Phibbs, C. S., Yong, C., Heidenreich, P. A., Turakhia, M. P. 2017; 119 (2): 268-274

    Abstract

    Warfarin prevents stroke and prolongs survival in patients with atrial fibrillation and flutter (AF, collectively) but can cause hemorrhage. The time in international normalized ratio (INR) therapeutic range (TTR) mediates stroke reduction and bleeding risk. This study sought to determine the relation between baseline stroke, bleeding risk, and TTR. Using data from The Retrospective Evaluation and Assessment of Therapies in Atrial Fibrillation (TREAT-AF) retrospective cohort study, national Veterans Health Administration records were used to identify patients with newly diagnosed AF from 2003 to 2012 and subsequent initiation of warfarin. Baseline stroke and bleeding risk was determined by calculating CHA2DS2-VASc and HAS-BLED scores, respectively. Main outcomes were first-year and long-term TTR and INR monitoring rate. In 167,190 patients, the proportion of patients with TTR (>65%) decreased across increasing strata of CHA2DS2-VASc and HAS-BLED. After covariate adjustment, odds of achieving TTR >65% were significantly associated with high CHA2DS2-VASc or HAS-BLED score. INR monitoring rate was similar across risk strata. In conclusion, increased baseline stroke and bleeding risk is associated with poor INR control, despite similar rates of INR monitoring. These findings may paradoxically limit warfarin's efficacy and safety in high-risk patients and may explain observed increased bleeding and stroke rates in this cohort.

    View details for DOI 10.1016/j.amjcard.2016.09.045

    View details for Web of Science ID 000392896900016

    View details for PubMedID 27836133

  • Atrial Fibrillation Diagnosis Timing, Ambulatory ECG Monitoring Utilization, and Risk of Recurrent Stroke CIRCULATION-CARDIOVASCULAR QUALITY AND OUTCOMES Lip, G. Y., Hunter, T. D., Quiroz, M. E., Ziegler, P. D., Turakhia, M. P. 2017; 10 (1)

    Abstract

    The risk of recurrence after an initial ischemic stroke or transient ischemic attack (TIA) may be impacted by undiagnosed atrial fibrillation (AF). We therefore assessed the impact of AF diagnosis and timing on stroke/TIA recurrence rates in a large real-world sample of patients.Using commercial claims data (Truven Health Analytics MarketScan), we performed a retrospective cohort study of patients with an index stroke or TIA event recorded in years 2008 through 2011. Patients were characterized by baseline oral anticoagulation, CHADS2 and CHA2DS2-VASc scores, AF diagnosis and timing with respect to the index stroke, and presence or absence of post-index ambulatory cardiac monitoring. The primary outcome was the recurrence of an ischemic stroke or TIA. Of 179 160 patients (age 67±16.2 years; 53.7% female), the Kaplan-Meier estimate for stroke/TIA recurrence within 1 year was 10.6%. Not having oral anticoagulation prescribed at baseline and having AF first diagnosed >7 days post-stroke (late AF) was highly associated with recurrent stroke/TIA (hazard ratio, 2.0; 95% confidence interval, 1.9-2.1). Among patients with at least 1 year of follow-up, only 2.6% and 9.7% had ambulatory ECG monitoring in the 7 days and 12 months post-stroke, respectively.AF diagnosed after stroke is an important hallmark of recurrent stroke risk. Increasing the low utilization of cardiac monitoring after stroke could identify undiagnosed AF earlier, leading to appropriate oral anticoagulation treatment and a reduction in stroke/TIA recurrence.

    View details for DOI 10.1161/CIRCOUTCOMES.116.002864

    View details for Web of Science ID 000394388600004

    View details for PubMedID 28096204

  • Survival After Secondary Prevention Implantable Cardioverter-Defibrillator Placement: An Analysis From the NCDR ICD Registry. JACC. Clinical electrophysiology Katz, D. F., Peterson, P., Borne, R. T., Betz, J., Al-Khatib, S. M., Varosy, P. D., Wang, Y., Hsu, J. C., Hoffmayer, K. S., Kipp, R. T., Hansen, C. M., Turakhia, M. P., Masoudi, F. A. 2017; 3 (1): 20–28

    Abstract

    OBJECTIVES: This study sought to define the characteristics and risks of death of patients receiving a physician-designated secondary prevention implantable cardioverter-defibrillator (ICD) in contemporary clinical practice.BACKGROUND: Data on utilization and outcomes of ICDs for the secondary prevention of sudden cardiac death (SCD) are limited.METHODS: Patients enrolled in the National Cardiovascular Data Registry's (NCDR) ICD Registry from 2006 to 2009 with a physician-designated secondary prevention indication for ICD implantation were identified and linked to the Social Security Death Master File. Those patients with a history either of tachycardic arrest or sustained ventricular tachycardia (SCD/VT) or of syncope without SCD/VT were included. Kaplan-Meier survival analysis was used to assess mortality. Cox proportional hazards survival modeling was used to assess the risk of death in these groups, adjusting for patient characteristics.RESULTS: In the study cohort of 46,685 patients (mean age 66 ± 14 years, 73.5% male, 85% white), 78% had SCD/VT and 22% had syncope. Overall mortality was 10.4% at 1 year and 16.4% at 2 years. Compared with patients having SCD/VT, the adjusted hazard of death at 1 year was lower in the patients having syncope (hazard ratio: 0.89; 95%confidence interval: 0.83 to 0.96) but was not significantly different by 2 years (hazard ratio: 0.96; 95% confidence interval: 0.90 to 1.01).CONCLUSIONS: Nearly 9 of 10 patients receiving a secondary prevention ICD in clinical practice are alive 1 year after implantation. The risk of death varies by indication and is highest among patients who survive SCD or sustained VT inthefirst year after device implantation.

    View details for DOI 10.1016/j.jacep.2016.06.001

    View details for PubMedID 29759690

  • IMPROVEMENT IN QUALITY OF CARE FOR ATRIAL FIBRILLATION IN GET WITH THE GUIDELINES- ATRIAL FIBRILLATION (GWTG-AFIB) Curtis, A. B., Piccini, J. P., Fonarow, G. C., Butler, J., Desai, N., Fang, M., McCabe, P., Page, R. L., Turakhia, M., Lewis, W. KARGER. 2017: 156
  • Safety and Clinical Outcomes of Catheter Ablation of Atrial Fibrillation in Patients With Chronic Kidney Disease JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY Ullal, A. J., Kaiser, D. W., Fan, J., Schmitt, S. K., Than, C. T., Winkelmayer, W. C., Heidenreich, P. A., Piccini, J. P., Perez, M. V., Wang, P. J., Turakhia, M. P. 2017; 28 (1): 39-48

    Abstract

    Data regarding catheter ablation of atrial fibrillation (AF) in patients with chronic kidney disease (CKD) is limited. We therefore assessed the association of CKD with common safety and clinical outcomes in a nationwide sample of ablation recipients.Using MarketScan(®) Commercial Claims and Medicare Supplemental Databases, we evaluated 30-day safety and 1-year clinical outcomes in patients who underwent a first AF ablation procedure between 2007 and 2011. We calculated frequency of common 30-day complications and calculated frequencies, incidence rates, and Cox proportional hazards for outcomes at 1-year postablation.Of 21,091 patients included, 1,593 (7.6%) had CKD. Patients with CKD were older (64 years vs. 59 years, P < 0.001) with higher CHA2 DS2 -VASc scores (3.2 vs. 1.8, P < 0.001). At 30 days postablation, patients with CKD had similar rates of stroke/TIA (0.13% vs. 0.13%, P = 0.99), perforation/tamponade (3.2% vs. 3.1%, P = 0.83), and vascular complications (2.4% vs. 2.2%, P = 0.59) as patients without CKD, but were more likely to be hospitalized for heart failure (2.1% vs. 0.4%, P < 0.001). In multivariate analysis, there were no significant differences in hazards of AF hospitalization (adjusted HR: 1.02, 95%CI: 0.87-1.20), cardioversion (adjusted HR: 0.99, 95%CI: 0.87-1.12), or repeat AF ablation (adjusted HR: 0.89, 95%CI: 0.76-1.06) at 1 year.Among patients selected for AF ablation, those with and without CKD had similar rates of postprocedural complications although they were more likely to be re-admitted for heart failure. CKD was not independently associated with AF hospitalization, cardioversion, and repeat ablation. These findings can inform clinical decision-making in patients with AF and CKD.

    View details for DOI 10.1111/jce.13118

    View details for Web of Science ID 000393901900004

  • International Collaborative Partnership for the Study of Atrial Fibrillation (INTERAF): Rationale, Design, and Initial Descriptives JOURNAL OF THE AMERICAN HEART ASSOCIATION Hsu, J. C., Akao, M., Abe, M., Anderson, K. L., Avezum, A., Glusenkamp, N., Kohsaka, S., Lane, D. A., Lip, G. H., Ma, C., Masoudi, F. A., Potpara, T. S., Siong, T., Turakhia, M. P., Tse, H., Rumsfeld, J. S., Maddox, T. M. 2016; 5 (11)
  • Safety and Clinical Outcomes of Catheter Ablation of Atrial Fibrillation in Patients with Chronic Kidney Disease. Journal of cardiovascular electrophysiology Ullal, A. J., Kaiser, D. W., Fan, J., Schmitt, S., Than, C. T., Winkelmayer, W. C., Heidenreich, P. A., Piccini, J. P., Perez, M. V., Wang, P. J., Turakhia, M. P. 2016

    Abstract

    Data regarding catheter ablation of atrial fibrillation (AF) in patients with chronic kidney disease (CKD) is limited. We therefore assessed the association of CKD with common safety and clinical outcomes in a nationwide sample of ablation recipients.Using MarketScan(®) Commercial Claims and Medicare Supplemental Databases, we evaluated 30-day safety and 1-year clinical outcomes in patients who underwent a first AF ablation procedure between 2007 and 2011. We calculated frequency of common 30-day complications and calculated frequencies, incidence rates, and Cox proportional hazards for outcomes at 1-year postablation.Of 21,091 patients included, 1,593 (7.6%) had CKD. Patients with CKD were older (64 years vs. 59 years, P < 0.001) with higher CHA2 DS2 -VASc scores (3.2 vs. 1.8, P < 0.001). At 30 days postablation, patients with CKD had similar rates of stroke/TIA (0.13% vs. 0.13%, P = 0.99), perforation/tamponade (3.2% vs. 3.1%, P = 0.83), and vascular complications (2.4% vs. 2.2%, P = 0.59) as patients without CKD, but were more likely to be hospitalized for heart failure (2.1% vs. 0.4%, P < 0.001). In multivariate analysis, there were no significant differences in hazards of AF hospitalization (adjusted HR: 1.02, 95%CI: 0.87-1.20), cardioversion (adjusted HR: 0.99, 95%CI: 0.87-1.12), or repeat AF ablation (adjusted HR: 0.89, 95%CI: 0.76-1.06) at 1 year.Among patients selected for AF ablation, those with and without CKD had similar rates of postprocedural complications although they were more likely to be re-admitted for heart failure. CKD was not independently associated with AF hospitalization, cardioversion, and repeat ablation. These findings can inform clinical decision-making in patients with AF and CKD.

    View details for DOI 10.1111/jce.13118

    View details for PubMedID 27782345

  • Transforming the care of atrial fibrillation with mobile health JOURNAL OF INTERVENTIONAL CARDIAC ELECTROPHYSIOLOGY Turakhia, M. P., Kaiser, D. W. 2016; 47 (1): 45-50

    Abstract

    Atrial fibrillation (AF) is a multifaceted and highly variable disease that is often difficult to manage within the traditional health-care model. The conventional model of regular or pre-scheduled appointments with physicians or allied health professionals is poorly suited to the unpredictable and often urgent clinical needs of patients with AF. Mobile health (mHealth) has the potential to dramatically transform the delivery and quality of AF care. In this brief review, we summarize the current limitations and evidence gaps in treating patients with AF. We then describe the current mHealth landscape, changes in telehealth coverage and reimbursement, and recent technological advances of smartphones, mobile applications, and connected wearable devices. We also describe important barriers and challenges, such as clinical management of large volumes of data, application of predictive analytics/machine learning, and the need for high-quality randomized clinical trials.

    View details for DOI 10.1007/s10840-016-0136-3

    View details for Web of Science ID 000387110400007

    View details for PubMedID 27306552

  • Reduced Mortality Associated WithQuadripolar Compared to BipolarLeftVentricular Leads in CardiacResynchronization Therapy. JACC. Clinical electrophysiology Turakhia, M. P., Cao, M., Fischer, A., Nabutovsky, Y., Sloman, L. S., Dalal, N., Gold, M. R. 2016; 2 (4): 426–33

    Abstract

    OBJECTIVES: The study sought to compare survival, lead deactivation, and lead replacement with quadripolar versusbipolar leads using a retrospective cohort of patients with newly implanted cardiac resynchronization therapy (CRT) systems.BACKGROUND: In CRT, quadripolar left ventricular (LV) leads offer alternative pacing sites and vectors not available with bipolar LV leads, which may improve the effectiveness of the therapy.METHODS: Using nationwide data from device implant registration records of a single manufacturer, we identified patients with a de novo cardiac resynchronization therapy with defibrillation (CRT-D) implanted between November 30, 2011, and May 31, 2013. Patients were followed for up to 24 months. The primary predictor was LV lead type (quadripolar Quartet [St. Jude Medical, St. Paul, Minnesota] LV lead or bipolar LV lead). The primary outcome was death and the secondary outcomes were LV lead replacement and deactivation.RESULTS: Among 23,570 patients (69.5 ± 11.1 years of age; 28% female; median follow-up time 1.14 years), 18,406 had quadripolar and 5,164 had bipolar LV leads. The quadripolar and bipolar groups had 5.04 and 6.45 deaths per 100 patient-years, respectively (p< 0.001). After multivariate adjustment, the quadripolar lead was associated with a lower risk of deactivation (hazard ratio [HR]: 0.62; 95% confidence interval [CI]: 0.46 to 0.84; p= 0.002), replacement (HR:0.67; 95% CI: 0.55 to 0.83; p< 0.001), and death (HR: 0.77; 95% CI: 0.69 to 0.86; p< 0.001).CONCLUSIONS: In this observational study of CRT-D devices, use of a quadripolar, compared to a bipolar LV lead, was associated with a reduction in LV lead deactivation, replacement, and mortality.

    View details for DOI 10.1016/j.jacep.2016.02.007

    View details for PubMedID 29759861

  • Cost-Effectiveness of Cardiac Radiosurgery for Atrial Fibrillation: Implications for Reducing Health Care Morbidity, Utilization, and Costs CUREUS Bhatt, N., Turakhia, M., Fogarty, T. J. 2016; 8 (8): e720

    Abstract

    In the United States (U.S.), atrial fibrillation (AF) is the second-most common cardiovascular condition after hypertension, affecting four million Americans each year. Individuals with AF are three times more likely to be hospitalized over the span of a year when compared to medically matched control groups. The considerably large clinical population of individuals with AF mandates that the cost-effectiveness and efficacy of current treatment regimens for AF have egregious implications for health care spending and public health. Unfortunately, catheter ablation for AF treatment has been shown to make only modest gains in quality-adjusted life years, has yet to demonstrate cost-utility advantages over conventional therapies for AF, and has a reported rate of recurrence for AF that is notably high. Thus, there is a major unmet clinical need for a therapeutic option to treat AF that produces more consistent and efficacious results that are cost-effective. Cardiac radiosurgery as a therapy for AF has the potential to be remarkably cost-effective and produce robust patient outcomes. CyberHeart Inc. has developed the world's first-ever cardiac radiosurgery (CRS) system designed to ablate the heart non-invasively. Procedures that ablate the heart utilizing the Cyberheart CRS system are anticipated to allow higher efficacy and more consistent results than current techniques such as catheter ablation. The aim of this study is to present the current healthcare utilization and expenditures in AF treatment, report the cost-effectiveness of catheter ablation for AF, and project the potential cost-effectiveness of cardiac radiosurgery for the treatment of AF.

    View details for DOI 10.7759/cureus.720

    View details for Web of Science ID 000453614700004

    View details for PubMedID 27625906

    View details for PubMedCentralID PMC5010376

  • Tecarfarin pharmacokinetics and pharmacodynamics-A novel CYP2C9 independent vitamin K antagonist Midei, M., Camm, A. J., Turakhia, M., Druzgala, P., Albrecht, D., Milner, P. OXFORD UNIV PRESS. 2016: 627–28
  • Aspirin Instead of Oral Anticoagulant Prescription in Atrial Fibrillation Patients at Risk for Stroke JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Hsu, J. C., Maddox, T. M., Kennedy, K., Katz, D. F., Marzec, L. N., Lubitz, S. A., Gehi, A. K., Turakhia, M. P., Marcus, G. M. 2016; 67 (25): 2913–23

    Abstract

    Oral anticoagulation (OAC), rather than aspirin, is recommended in patients with atrial fibrillation (AF) at moderate to high risk of stroke.This study sought to examine patient and practice-level factors associated with prescription of aspirin alone compared with OAC in AF patients at intermediate to high stroke risk in real-world cardiology practices.The authors identified 2 cohorts of outpatients with AF and intermediate to high thromboembolic risk (CHADS2 score ≥2 and CHA2DS2-VASc ≥2) enrolled in the American College of Cardiology PINNACLE (Practice Innovation and Clinical Excellence) registry between 2008 and 2012. Using hierarchical modified Poisson regression models adjusted for patient and practice characteristics, the authors examined the prevalence and predictors of aspirin alone versus OAC prescription in AF patients at risk for stroke.Of 210,380 identified patients with CHADS2 score ≥2 on antithrombotic therapy, 80,371 (38.2%) were treated with aspirin alone, and 130,009 (61.8%) were treated with warfarin or non-vitamin K antagonist OACs. In the cohort of 294,642 patients with CHA2DS2-VASc ≥2, 118,398 (40.2%) were treated with aspirin alone, and 176,244 (59.8%) were treated with warfarin or non-vitamin K antagonist OACs. After multivariable adjustment, hypertension, dyslipidemia, coronary artery disease, prior myocardial infarction, unstable and stable angina, recent coronary artery bypass graft, and peripheral arterial disease were associated with prescription of aspirin only, whereas male sex, higher body mass index, prior stroke/transient ischemic attack, prior systemic embolism, and congestive heart failure were associated with more frequent prescription of OAC.In a large, real-world cardiac outpatient population of AF patients with a moderate to high risk of stroke, more than 1 in 3 were treated with aspirin alone without OAC. Specific patient characteristics predicted prescription of aspirin therapy over OAC.

    View details for DOI 10.1016/j.jacc.2016.03.581

    View details for Web of Science ID 000378053500001

    View details for PubMedID 27339487

  • Comparative Effectiveness of Cardiac Resynchronization Therapy Among Patients With Heart Failure and Atrial Fibrillation Findings From the National Cardiovascular Data Registry's Implantable Cardioverter-Defibrillator Registry CIRCULATION-HEART FAILURE Khazanie, P., Greiner, M. A., Al-Khatib, S. M., Piccini, J. P., Turakhia, M. P., Varosy, P. D., Masoudi, F. A., Curtis, L. H., Hernandez, A. F. 2016; 9 (6)

    Abstract

    Atrial fibrillation is common in patients with heart failure, but outcomes of patients with both conditions who receive cardiac resynchronization therapy with defibrillator (CRT-D) compared with an implantable cardioverter-defibrillator (ICD) alone are unclear.Using the National Cardiovascular Data Registry's ICD Registry linked with Medicare claims, we identified 8951 patients with atrial fibrillation who were eligible for CRT-D and underwent first-time device implantation for primary prevention between April 2006 and December 2009. We used Cox proportional hazards models and inverse probability-weighted estimates to compare outcomes with CRT-D versus ICD alone. Cumulative incidence of mortality (744 [33%] for ICD; 1893 [32%] for CRT-D) and readmission (1788 [76%] for ICD; 4611 [76%] for CRT-D) within 3 years and complications within 90 days were similar between groups. After inverse weighting for the probability of receiving CRT-D, risks of mortality (hazard ratio, 0.83; 95% confidence interval, 0.75-0.92), all-cause readmission (hazard ratio, 0.86; 95% confidence interval, 0.80-0.92), and heart failure readmission (hazard ratio, 0.68; 95% confidence interval, 0.62-0.76) were lower with CRT-D compared with ICD alone. There was no significant difference in the 90-day complication rate (hazard ratio, 0.88; 95% confidence interval, 0.60-1.29). We observed hospital-level variation in the use of CRT-D among patients with atrial fibrillation.Among eligible patients with heart failure and atrial fibrillation, CRT-D was associated with lower risks of mortality, all-cause readmission, and heart failure readmission, as well as with a similar risk of complications compared with ICD alone.

    View details for DOI 10.1161/CIRCHEARTFAILURE.115.002324

    View details for Web of Science ID 000378139000001

    View details for PubMedID 27296396

    View details for PubMedCentralID PMC4910638

  • Cost-Effectiveness of Implantable Pulmonary Artery Pressure Monitoring in Chronic Heart Failure JACC-HEART FAILURE Sandhu, A. T., Goldhaber-Fiebert, J. D., Owens, D. K., Turakhia, M. P., Kaiser, D. W., Heidenreich, P. A. 2016; 4 (5): 368-375

    Abstract

    This study aimed to evaluate the cost-effectiveness of the CardioMEMS (CardioMEMS Heart Failure System, St Jude Medical Inc, Atlanta, Georgia) device in patients with chronic heart failure.The CardioMEMS device, an implantable pulmonary artery pressure monitor, was shown to reduce hospitalizations for heart failure and improve quality of life in the CHAMPION (CardioMEMS Heart Sensor Allows Monitoring of Pressure to Improve Outcomes in NYHA Class III Heart Failure Patients) trial.We developed a Markov model to determine the hospitalization, survival, quality of life, cost, and incremental cost-effectiveness ratio of CardioMEMS implantation compared with usual care among a CHAMPION trial cohort of patients with heart failure. We obtained event rates and utilities from published trial data; we used costs from literature estimates and Medicare reimbursement data. We performed subgroup analyses of preserved and reduced ejection fraction and an exploratory analysis in a lower-risk cohort on the basis of the CHARM (Candesartan in Heart failure: Reduction in Mortality and Morbidity) trials.CardioMEMS reduced lifetime hospitalizations (2.18 vs. 3.12), increased quality-adjusted life-years (QALYs) (2.74 vs. 2.46), and increased costs ($176,648 vs. $156,569), thus yielding a cost of $71,462 per QALY gained and $48,054 per life-year gained. The cost per QALY gained was $82,301 in patients with reduced ejection fraction and $47,768 in those with preserved ejection fraction. In the lower-risk CHARM cohort, the device would need to reduce hospitalizations for heart failure by 41% to cost <$100,000 per QALY gained. The cost-effectiveness was most sensitive to the device's durability.In populations similar to that of the CHAMPION trial, the CardioMEMS device is cost-effective if the trial effectiveness is sustained over long periods. Post-marketing surveillance data on durability will further clarify its value.

    View details for DOI 10.1016/j.jchf.2015.12.015

    View details for Web of Science ID 000375347200006

    View details for PubMedID 26874380

    View details for PubMedCentralID PMC4851610

  • Health Care Utilization and Expenditures Associated With Remote Monitoring in Patients With Implantable Cardiac Devices AMERICAN JOURNAL OF CARDIOLOGY Ladapo, J. A., Turakhia, M. P., Ryan, M. P., Mollenkopf, S. A., Reynolds, M. R. 2016; 117 (9): 1455–62

    Abstract

    Several randomized trials and decision analysis models have found that remote monitoring may reduce health care utilization and expenditures in patients with cardiac implantable electronic devices (CIEDs), compared with in-office monitoring. However, little is known about the generalizability of these findings to unselected populations in clinical practice. To compare health care utilization and expenditures associated with remote monitoring and in-office monitoring in patients with CIEDs, we used Truven Health MarketScan Commercial Claims and Medicare Supplemental Databases. We selected patients newly implanted with an implantable cardioverter defibrillators (ICD), cardiac resynchronization therapy defibrillator (CRT-D), or permanent pacemaker (PPM), in 2009, who had continuous health plan enrollment 2 years after implantation. Generalized linear models and propensity score matching were used to adjust for confounders and estimate differences in health care utilization and expenditures in patients with remote or in-office monitoring. We identified 1,127; 427; and 1,295 pairs of patients with a similar propensity for receiving an ICD, CRT-D, or PPM, respectively. Remotely monitored patients with ICDs experienced fewer emergency department visits resulting in discharge (p = 0.050). Remote monitoring was associated with lower health care expenditures in office visits among patients with PPMs (p = 0.025) and CRT-Ds (p = 0.006) and lower total inpatient and outpatient expenditures in patients with ICDs (p <0.0001). In conclusion, remote monitoring of patients with CIEDs may be associated with reductions in health care utilization and expenditures compared with exclusive in-office care.

    View details for DOI 10.1016/j.amjcard.2016.02.015

    View details for Web of Science ID 000384514300011

    View details for PubMedID 26996767

  • ASSOCIATION OF INSURANCE TYPE WITH RECEIPT OF ORAL ANTICOAGULATION IN ATRIAL FIBRILLATION: AN ANALYSIS OF THE AMERICAN COLLEGE OF CARDIOLOGY NCDR PINNACLE REGISTRY Yong, C. M., Liu, Y., Lei, L., Doros, G., Cannon, C., Maddox, T., Gehi, A., Virani, S., Turakhia, M., ACC PINNACLE Investigators ELSEVIER SCIENCE INC. 2016: 888
  • Oral Anticoagulant Therapy Prescription in Patients With Atrial Fibrillation Across the Spectrum of Stroke Risk Insights From the NCDR PINNACLE Registry JAMA CARDIOLOGY Hsu, J. C., Maddox, T. M., Kennedy, K. F., Katz, D. F., Marzec, L. N., Lubitz, S. A., Gehi, A. K., Turakhia, M. P., Marcus, G. M. 2016; 1 (1): 55–62

    Abstract

    Patients with atrial fibrillation (AF) are at a proportionally higher risk of stroke based on accumulation of well-defined risk factors.To examine the extent to which prescription of an oral anticoagulant (OAC) in US cardiology practices increases as the number of stroke risk factors increases.Cross-sectional registry study of outpatients with AF enrolled in the American College of Cardiology National Cardiovascular Data Registry's PINNACLE (Practice Innovation and Clinical Excellence) Registry between January 1, 2008, and December 30, 2012. As a measure of stroke risk, we calculated the CHADS2 score and the CHA2DS2-VASc score for all patients. Using multinomial logistic regression models adjusted for patient, physician, and practice characteristics, we examined the association between increased stroke risk score and prescription of an OAC.The primary outcome was prescription of an OAC with warfarin sodium or a non-vitamin K antagonist OAC.The study cohort comprised 429 417 outpatients with AF. Their mean (SD) age was 71.3 (12.9) years, and 55.8% were male. Prescribed treatment consisted of an OAC (192 600 [44.9%]), aspirin only (111 134 [25.9%]), aspirin plus a thienopyridine (23 454 [5.5%]), or no antithrombotic therapy (102 229 [23.8%]). Each 1-point increase in risk score was associated with increased odds of OAC prescription compared with aspirin-only prescription using the CHADS2 score (adjusted odds ratio, 1.158; 95% CI, 1.144-1.172; P < .001) and the CHA2DS2-VASc score (adjusted odds ratio, 1.163; 95% CI, 1.157-1.169; P < .001). Overall, OAC prescription prevalence did not exceed 50% even in higher-risk patients with a CHADS2 score exceeding 3 or a CHA2DS2-VASc score exceeding 4.In a large quality improvement registry of outpatients with AF, prescription of OAC therapy increased with a higher CHADS2 score and CHA2DS2-VASc score. However, a plateau of OAC prescription was observed, with less than half of high-risk patients receiving an OAC prescription.

    View details for DOI 10.1001/jamacardio.2015.0374

    View details for Web of Science ID 000400438400011

    View details for PubMedID 27437655

  • The precise timing of tachycardia entrainment is determined by the postpacing interval, the tachycardia cycle length, and the pacing rate: Theoretical insights and practical applications HEART RHYTHM Kaiser, D. W., Hsia, H. H., Dubin, A. M., Liem, L. B., Viswanathan, M. N., Zei, P. C., Wang, P. J., Narayan, S. M., Turakhia, M. P. 2016; 13 (3): 695-703

    Abstract

    Previous observations have reported that the number of pacing stimuli required to entrain a tachycardia varies on the basis of arrhythmia type and location, but a quantitative formulation of the number needed to entrain (NNE) that unifies these observations has not been characterized.We sought to investigate the relationship between the number of pacing stimulations, the tachycardia cycle length (TCL), the overdrive pacing cycle length (PCL), and the postpacing interval (PPI) to accurately estimate the timing of tachycardia entrainment.First, we detailed a mathematical derivation unifying electrophysiological parameters with empirical confirmation in 2 patients undergoing catheter ablation of typical atrial flutter. Second, we validated our formula in 44 patients who underwent various catheter ablation procedures. For accuracy, we corrected for rate-related changes in conduction velocity.We derived the equations NNE = |(PPI - TCL)/(TCL - PCL)| + 1 and Tachycardia advancement = (NNE - 1) × (TCL - PCL) - (PPI - TCL), which state that the NNE and the amount of tachycardia advancement on the first resetting stimulation are determined using regularly measured intracardiac parameters. In the retrospective cohort, the observed PPI - TCL highly correlated with the predicted PPI - TCL (mean difference 5.8 ms; r = 0.97; P < .001), calculated as PPI - TCL = (NNE - 1) × (TCL - PCL) - tachycardia advancement.The number of pacing stimulations required to entrain a reentrant tachycardia is predictable at any PCL after correcting for cycle length-dependent changes in conduction velocity. This relationship unifies established empirically derived diagnostic and mapping criteria for supraventricular tachycardia and ventricular tachycardia. This relationship may help elucidate when antitachycardia pacing episodes are ineffective or proarrhythmic and could potentially serve as a theoretical basis to customize antitachycardia pacing settings for improved safety and effectiveness.

    View details for DOI 10.1016/j.hrthm.2015.11.032

    View details for Web of Science ID 000372367800012

    View details for PubMedCentralID PMC4770895

  • Stroke Risk Stratification in Atrial Fibrillation: Bridging the Evidence Gaps JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY Turakhia, M. P., Estes, N. 2016; 27 (3): 271–73

    View details for DOI 10.1111/jce.12891

    View details for Web of Science ID 000372648600007

    View details for PubMedID 26643150

  • Sleep disordered breathing and cardiovascular risk in older patients initiating dialysis in the United States: a retrospective observational study using medicare data BMC NEPHROLOGY Tuohy, C. V., Montez-Rath, M. E., Turakhia, M., Chang, T. I., Winkelman, J. W., Winkelmayer, W. C. 2016; 17
  • Racial Differences in Quality of Anticoagulation Therapy for Atrial Fibrillation (from the TREAT-AF Study) AMERICAN JOURNAL OF CARDIOLOGY Yong, C., Azarbal, F., Abnousi, F., Heidenreich, P. A., Schmitt, S., Fan, J., Than, C. T., Ullal, A. J., Yang, F., Phibbs, C. S., Frayne, S. M., Ho, P. M., Shore, S., Mahaffey, K. W., Turakhia, M. P. 2016; 117 (1): 61-68

    Abstract

    The influence of race on quality of anticoagulation control is not well described. We examined the association between race, international normalized ratio (INR) monitoring intensity, and INR control in warfarin-treated patients with atrial fibrillation (AF). Using data from the Veterans Health Administration (VHA), we performed a retrospective cohort study of 184,161 patients with a new diagnosis of AF/flutter from 2004 to 2012 who received any VHA prescription within 90 days of diagnosis. The primary predictor was race, ascertained from multiple VHA and linked Medicare demographic files. The primary outcome was first-year and long-term time in therapeutic range (TTR) of INR 2.0 to 3.0. Secondary outcomes were INR monitoring intensity and warfarin persistence. Of the 116,021 patients who received warfarin in the cohort, INR monitoring intensity was similar across racial groups. However, TTR was lowest in blacks and highest in whites (first year 0.49 ± 0.23 vs 0.57 ± 0.21, p <0.001; long term 0.52 ± 0.20 vs 0.59 ± 0.18, p <0.001); 64% of whites and 49% of blacks had long-term TTR >55% (p <0.001). After adjusting for site and patient-level covariates, black race was associated with lower first-year and long-term TTRs (4.2% and 4.1% below the conditional mean, relative to whites; p <0.0001 for both). One-year warfarin persistence was slightly lower in blacks compared to whites (58% vs 60%, p <0.0001). In conclusion, in patients with AF anticoagulated with warfarin, differences in INR control are most evident among blacks, underscoring the need to determine if other types of intensive management or warfarin alternatives may be necessary to improve anticoagulation among vulnerable AF populations.

    View details for DOI 10.1016/j.amjcard.2015.09.047

    View details for Web of Science ID 000368048900010

  • Gender Differences in Clinical Outcomes After Catheter Ablation of Atrial Fibrillation JACC Clin Electrophysiol Kaiser, D. W., Fan, J., Schmitt, S., Than, C. T., Ullal, A. J., Piccini, J. P., Heidenreich, P. A., Turakhia, M. P. 2016
  • Utilization and Likelihood of Radiologic Diagnostic Imaging in Patients With Implantable Cardiac Defibrillators JOURNAL OF MAGNETIC RESONANCE IMAGING Nazarian, S., Reynolds, M. R., Ryan, M. P., Wolff, S. D., Mollenkopf, S. A., Turakhia, M. P. 2016; 43 (1): 115–27

    Abstract

    To examine imaging utilization in a matched cohort of patients with and without implantable cardioverter defibrillators (ICD) and to project magnetic resonance imaging (MRI) utilization over a 10-year period.The Truven Health MarketScan Commercial claims and Medicare Supplemental health insurance claims data were used to identify patients with continuous health plan enrollment in 2009-2012. Patients with ICDs were identified using ICD-9 and CPT codes, and matched to patients with the same demographic and comorbidity profile, but no record of device implantation. Diagnostic imaging utilization was compared across the matched cohorts, in total, by imaging categories, and in subpopulations of stroke, back pain, and joint pain. MRI use in the nonimplant group over the 4-year period was extrapolated out to 10 years for ICD-indicated patients.A cohort of 18,770 matched patients were identified; average age 65.5 ± 13.38 and 21.9% female. ICD patients had significantly less MRI imaging (0.23 0.70 SD vs. 0.00 0.08 SD, P < 0.0001) than nonimplant patients. Among patients with records of stroke/transient ischemic attack (TIA) (ICD 5%, nonimplant 4%) and accompanying diagnostic imaging, 44% of nonimplant patients underwent MRI vs. 1% of ICD patients (P < 0.0001). Forecast models estimated that 53% to 64% of ICD-eligible patients may require an MRI within 10 years.MRI utilization is lower in ICD patients compared to nonimplant patients, yet the burden of incident stroke/TIA, back, and joint pain suggests an unmet need for MR-conditional devices.

    View details for DOI 10.1002/jmri.24971

    View details for Web of Science ID 000368741400010

    View details for PubMedID 26118943

    View details for PubMedCentralID PMC4755166

  • International Collaborative Partnership for the Study of Atrial Fibrillation (INTERAF): Rationale, Design, and Initial Descriptives. Journal of the American Heart Association Hsu, J. C., Akao, M., Abe, M., Anderson, K. L., Avezum, A., Glusenkamp, N., Kohsaka, S., Lane, D. A., Lip, G. Y., Ma, C., Masoudi, F. A., Potpara, T. S., Siong, T. W., Turakhia, M. P., Tse, H., Rumsfeld, J. S., Maddox, T. M. 2016; 5 (11)

    View details for PubMedID 27806965

  • Amiodarone and risk of death in contemporary patients with atrial fibrillation: Findings from The Retrospective Evaluation and Assessment of Therapies in AF study. American heart journal Ullal, A. J., Than, C. T., Fan, J., Schmitt, S., Perino, A. C., Kaiser, D. W., Heidenreich, P. A., Frayne, S. M., Phibbs, C. S., Turakhia, M. P. 2015; 170 (5): 1033-1041 e1

    Abstract

    There are limited data on mortality outcomes associated with use of amiodarone in atrial fibrillation and flutter (AF).We evaluated the association of amiodarone use with mortality in patients with newly diagnosed AF using complete data from the Department of Veterans Affairs national health care system. We included patients seen in an outpatient setting within 90 days of a new diagnosis for nonvalvular AF between Veterans Affairs fiscal years 2004 and 2008. Multivariate analysis and propensity-matched Cox proportional hazards regression were used to evaluate the association of amiodarone use to death.Of 122,465 patients (353,168 person-years of follow-up, age 72.1 ± 10.3 years, 98.4% males), amiodarone was prescribed in 11,655 (9.5%). Cumulative, unadjusted mortality rates were higher for amiodarone recipients than for nonrecipients (87 vs 73 per 1,000 person-years, P < .001). However, in multivariate and propensity-matched survival analyses, there was no significant difference in mortality (multivariate hazard ratio 1.01, 95% CI 0.97-1.05, P = .51, and propensity-matched hazard ratio 1.02, 95% CI 0.97-1.07, P = .45). The hazard of death was not modified by age, sex, heart failure, kidney function, β-blocker use, or warfarin use, but there was evidence of effect modification among patients diagnosed with AF as an inpatient versus outpatient.In a national health care system population of newly diagnosed AF, overall use of amiodarone as an early treatment strategy was not associated with mortality.

    View details for DOI 10.1016/j.ahj.2015.07.023

    View details for PubMedID 26542514

    View details for PubMedCentralID PMC4800972

  • Innovative designs of point-of-care comparative effectiveness trials CONTEMPORARY CLINICAL TRIALS Shih, M., Turakhia, M., Lai, T. L. 2015; 45: 61-68

    Abstract

    One of the provisions of the health care reform legislation in 2010 was for funding pragmatic clinical trials or large observational studies for comparing the effectiveness of different approved medical treatments, involving broadly representative patient populations. After reviewing pragmatic clinical trials and the issues and challenges that have made them just a small fraction of comparative effectiveness research (CER), we focus on a recent development that uses point-of-care (POC) clinical trials to address the issue of "knowledge-action gap" in pragmatic CER trials. We give illustrative examples of POC-CER trials and describe a trial that we are currently planning to compare the effectiveness of newly approved oral anticoagulants. We also develop novel stage-wise designs of information-rich POC-CER trials under competitive budget constraints, by using recent advances in adaptive designs and other statistical methodologies.

    View details for DOI 10.1016/j.cct.2015.06.014

    View details for Web of Science ID 000367754700010

    View details for PubMedCentralID PMC4639459

  • Amiodarone and risk of death in contemporary patients with atrial fibrillation: Findings from The Retrospective Evaluation and Assessment of Therapies in AF study AMERICAN HEART JOURNAL Ullal, A. J., Than, C. T., Fan, J., Schmitt, S., Perino, A. C., Kaiser, D. W., Heidenreich, P. A., Frayne, S. M., Phibbs, C. S., Turakhia, M. P. 2015; 170 (5): 1033-U231

    Abstract

    There are limited data on mortality outcomes associated with use of amiodarone in atrial fibrillation and flutter (AF).We evaluated the association of amiodarone use with mortality in patients with newly diagnosed AF using complete data from the Department of Veterans Affairs national health care system. We included patients seen in an outpatient setting within 90 days of a new diagnosis for nonvalvular AF between Veterans Affairs fiscal years 2004 and 2008. Multivariate analysis and propensity-matched Cox proportional hazards regression were used to evaluate the association of amiodarone use to death.Of 122,465 patients (353,168 person-years of follow-up, age 72.1 ± 10.3 years, 98.4% males), amiodarone was prescribed in 11,655 (9.5%). Cumulative, unadjusted mortality rates were higher for amiodarone recipients than for nonrecipients (87 vs 73 per 1,000 person-years, P < .001). However, in multivariate and propensity-matched survival analyses, there was no significant difference in mortality (multivariate hazard ratio 1.01, 95% CI 0.97-1.05, P = .51, and propensity-matched hazard ratio 1.02, 95% CI 0.97-1.07, P = .45). The hazard of death was not modified by age, sex, heart failure, kidney function, β-blocker use, or warfarin use, but there was evidence of effect modification among patients diagnosed with AF as an inpatient versus outpatient.In a national health care system population of newly diagnosed AF, overall use of amiodarone as an early treatment strategy was not associated with mortality.

    View details for DOI 10.1016/j.ahj.2015.07.023

    View details for Web of Science ID 000364434600026

    View details for PubMedID 26542514

    View details for PubMedCentralID PMC4800972

  • Outcomes After Warfarin Initiation in a Cohort of Hemodialysis Patients With Newly Diagnosed Atrial Fibrillation. American journal of kidney diseases Shen, J. I., Montez-Rath, M. E., Lenihan, C. R., Turakhia, M. P., Chang, T. I., Winkelmayer, W. C. 2015; 66 (4): 677-688

    Abstract

    Although warfarin is indicated to prevent ischemic strokes in most patients with atrial fibrillation (AF), evidence supporting its use in hemodialysis patients is limited. Our aim was to examine outcomes after warfarin therapy initiation, relative to no warfarin use, following incident AF in a large cohort of hemodialysis patients who had comprehensive prescription drug coverage through Medicare Part D.Retrospective observational cohort study.Patients in the US Renal Data System undergoing maintenance hemodialysis who had AF newly diagnosed in 2007 to 2011, with Medicare Part D coverage, who had no recorded history of warfarin use.Warfarin therapy initiation, identified by a filled prescription within 30 days of the AF event.Death, ischemic stroke, hemorrhagic stroke, severe gastrointestinal bleeding, and composite outcomes.HRs estimated by applying Cox regression to an inverse probability of treatment and censoring-weighted cohort.Of 12,284 patients with newly diagnosed AF, 1,838 (15%) initiated warfarin therapy within 30 days; however, ∼70% discontinued its use within 1 year. In intention-to-treat analyses, warfarin use was marginally associated with a reduced risk of ischemic stroke (HR, 0.68; 95% CI, 0.47-0.99), but not with the other outcomes. In as-treated analyses, warfarin use was associated with reduced mortality (HR, 0.84; 95% CI, 0.73-0.97).Short observation period, limited number of nonfatal events, limited generalizability of results to more affluent patients.In hemodialysis patients with incident AF, warfarin use was marginally associated with reduced risk of ischemic stroke, and there was a signal toward reduced mortality in as-treated analyses. These results support clinical equipoise regarding the use of warfarin in hemodialysis patients and underscore the need for randomized trials to fill this evidence gap.

    View details for DOI 10.1053/j.ajkd.2015.05.019

    View details for PubMedID 26162653

  • Atrial Fibrillation Burden and Short-Term Risk of Stroke Case-Crossover Analysis of Continuously Recorded Heart Rhythm From Cardiac Electronic Implanted Devices CIRCULATION-ARRHYTHMIA AND ELECTROPHYSIOLOGY Turakhia, M. P., Ziegler, P. D., Schmitt, S. K., Chang, Y., Fan, J., Than, C. T., Keung, E. K., Singer, D. E. 2015; 8 (5): 1040-1047

    Abstract

    The temporal relationship of atrial fibrillation (AF) and stroke risk is controversial. We evaluated this relationship via a case-crossover analysis of ischemic strokes in a large cohort of patients with cardiac implantable electronic devices.We identified 9850 patients with cardiac implantable electronic devices remotely monitored in the Veterans Administration Health Care System between 2002 and 2012. There were 187 patients with acute ischemic stroke and continuous heart rhythm monitoring for 120 days before the stroke (age, 69±8.4 years; 98% with an implantable defibrillator). We compared each patient's daily AF burden in the 30 days before stroke (case period) with their AF burden during days 91 to 120 pre stroke (control period). Defining positive AF burden as ≥5.5 hours of AF on any given day, 156 patients (83%) had no positive AF burden in both periods and, in fact, had little to no AF; 15 (8%) patients had positive AF burden in both periods. Among the discordant (informative) patients, 13 exceeded 5.5 hours of AF in the case period but not in the control period, whereas 3 had positive AF burden in the control but not in the case period (warfarin-adjusted odds ratio for stroke, 4.2; 95% confidence interval, 1.5-13.4). Odds ratio for stroke was highest (17.4; 95% confidence interval, 5.39-73.1) in the 5 days immediately after a qualifying occurrence of AF and decreased toward 1.0 as the period after the AF occurrence increased beyond 30 days.In this population with continuous heart rhythm recording, multiple hours of AF had a strong but transient effect raising stroke risk.

    View details for DOI 10.1161/CIRCEP.114.003057

    View details for Web of Science ID 000363374100010

    View details for PubMedID 26175528

  • Defibrillator implantations for primary prevention in the United States: Inappropriate care or inadequate documentation: Insights from the National Cardiovascular Data ICD Registry. Heart rhythm Kaiser, D. W., Tsai, V., Heidenreich, P. A., Goldstein, M. K., Wang, Y., Curtis, J., Turakhia, M. P. 2015; 12 (10): 2086-2093

    Abstract

    Prior studies have reported that more than 20% of implantable cardioverter-defibrillator (ICD) implantations in the United States do not adhere to trial-based criteria.We sought to investigate the patient characteristics associated with not meeting the inclusion criteria of the clinical trials that have demonstrated the efficacy of primary prevention ICDs.Using data from the National Cardiovascular Data Registry's ICD Registry, we identified patients who received ICDs for primary prevention from January 2006 to December 2008. We determined whether patients met the inclusion criteria of at least 1 of the 4 ICD primary prevention trials: Multicenter Automatic Defibrillator Implantation Trial (MADIT), MADIT-II, Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT), and the Multicenter Unsustained Tachycardia Trial (MUSTT).Among 150,264 patients, 86% met criteria for an ICD implantation based on trial data. The proportion of patients who did not meet trial-based criteria increased as age decreased. In multivariate analysis, the significant predictors for not meeting trial criteria included prior cardiac transplantation (odds ratio [OR] 2.1), pediatric electrophysiology operator (OR 2.0), and high-grade atrioventricular conduction disease (OR 1.4).Among National Cardiovascular Data Registry registrants receiving first-time ICDs for primary prevention, the majority met trial-based criteria. Multivariate analyses suggested that many patients who did not meet the trial-based criteria may have had clinical circumstances that warranted ICD implantation. These findings caution against the use of trial-based indications to determine site quality metrics that could penalize sites that care for younger patients. The planned incorporation of appropriate use criteria into the ICD registry may better characterize patient- and site-level quality and performance.

    View details for DOI 10.1016/j.hrthm.2015.05.010

    View details for PubMedID 25982720

    View details for PubMedCentralID PMC4770888

  • Economic Burden of Undiagnosed Nonvalvular Atrial Fibrillation in the United States AMERICAN JOURNAL OF CARDIOLOGY Turakhia, M. P., Shafrin, J., Bognar, K., Goldman, D. P., Mendys, P. M., Abdulsattar, Y., Wiederkehr, D., Trocio, J. 2015; 116 (5): 733-739

    Abstract

    Atrial fibrillation (AF) may be clinically silent and therefore undiagnosed. To date, no estimates of the direct medical cost of undiagnosed AF exist. We estimated the United States (US) incremental cost burden of undiagnosed nonvalvular AF nationally using administrative claims data. To calculate the incremental costs of undiagnosed AF, we compared annual medical costs (in 2014 US Dollars) for patients with AF compared to propensity-matched controls and multiplied this by estimates of undiagnosed AF prevalence derived from the same data sources. The study population included US residents aged ≥18 years with 24 months of continuous enrollment drawn from 2 large administrative claims databases. Mean per capita medical spending for patients with AF aged from 18 to 64 year was $38,861 (95% confidence interval [CI] $35,781 to $41,950) compared to $28,506 (95% CI $28,409 to $28,603) for similar patients without AF (incremental cost difference $10,355, p <0.001); total spending for patients aged ≥65 years with AF was $25,322 (95% CI $25,049 to $25,595) compared to $21,706 (95% CI $21,563 to $21,849) for similar patients without AF (incremental cost difference $3,616, p <0.001). Using estimates of the US prevalence of undiagnosed AF (596,000) drawn from the same data, we estimated that the US incremental cost burden of undiagnosed nonvalvular AF is $3.1 billion (95% CI $2.7 to $3.7 billion). In conclusion, the direct medical costs for patients with undiagnosed AF are greater than patients with similar observable characteristics without AF and strategies to identify and treat patients with undiagnosed AF could lead to sizable reductions in stroke sequelae and associated costs.

    View details for DOI 10.1016/j.amjcard.2015.05.045

    View details for Web of Science ID 000361270100011

    View details for PubMedID 26138378

  • A validated risk model for 1-year mortality after primary prevention implantable cardioverter defibrillator placement AMERICAN HEART JOURNAL Heidenreich, P. A., Tsai, V., Curtis, J., Wang, Y., Turakhia, M. P., Masoudi, F. A., Varosy, P. D., Goldstein, M. K. 2015; 170 (2): 281-U119

    Abstract

    We sought to determine survival for patients with heart failure after an implantation of an implantable cardioverter defibrillator (ICD) for primary prevention in the United States and to develop a simple model that would predict mortality risk.Clinical trials have found that patients with heart failure with a 1-year mortality risk near 20% may not benefit from an ICD.We identified patients from the ICD Registry of the National Cardiovascular Disease Registries who underwent ICD implantation for primary prevention from 2007 to 2009. Two risk scores for mortality were developed in 2 cohorts: one limited to those with a B-type natriuretic peptide (BNP) value and a second for all patients. The scores were obtained from derivation datasets and tested in a validation sets using logistic regression models and classification and regression trees.In a primary prevention population with BNP available (18,725) the 6 variables most predictive of 1-year mortality were age ≥75, BNP ≥700 pg/mL, chronic lung disease, dialysis, blood urea nitrogen ≥30 mg/dL, and systolic blood pressure <120 mmHg. Patients with zero risk factors had a 3.3% one-year mortality compared to a 66.7% one-year mortality for those with all 6 risk factors. Those with ≥3 risk factors (24.0% of the population) had a 25.8% one-year mortality. A second score using a larger cohort that did not consider BNP identified similar risk factors.A simple validated risk score can identify patients at high and low risk for death within a year after ICD placement. A large fraction of those currently implanted with an ICD in the United States have a high 1-year mortality and may not benefit from ICD therapy.

    View details for DOI 10.1016/j.ahj.2014.12.013

    View details for Web of Science ID 000360360100015

  • Early detection of occult atrial fibrillation and stroke prevention HEART Keach, J. W., Bradley, S. M., Turakhia, M. P., Maddox, T. M. 2015; 101 (14): 1097-1102

    Abstract

    Atrial fibrillation (AF) is a very common arrhythmia and significantly increases stroke risk. This risk can be mitigated with oral anticoagulation, but AF is often asymptomatic, or occult, preventing timely detection and treatment. Accordingly, occult AF may cause stroke before it is clinically diagnosed. Currently, guidelines for the early detection and treatment of occult AF are limited. This review addresses recent advancements in occult AF detection methods, identification of populations at high risk for occult AF, the treatment of occult AF with oral anticoagulation, as well as ongoing trials that may answer critically important questions regarding occult AF screening.

    View details for DOI 10.1136/heartjnl-2015-307588

    View details for Web of Science ID 000357038700007

    View details for PubMedID 25935765

  • Individual and Combined Risk Factors for Incident Atrial Fibrillation and Incident Stroke: An Analysis of 3 Million At-Risk US Patients JOURNAL OF THE AMERICAN HEART ASSOCIATION Chyou, J. Y., Hunter, T. D., Mollenkopf, S. A., Turakhia, M. P., Reynolds, M. R. 2015; 4 (7)

    Abstract

    The incremental effects of risk factor combinations for atrial fibrillation (AF) and stroke are incompletely understood. We sought to quantify the risks of incident AF and stroke for combinations of established risk factors in a large US sample.Patients with no evidence of AF or stroke in 2007 were stratified by combinations of the following risk factors: heart failure, hypertension, diabetes, age 65 to 74, age ≥75, coronary artery disease, and chronic kidney disease. Patients with ≥2 of the first 5 or ≥3 of the first 7, classified as "high-risk," and an age-matched sample of patients with fewer risk factors, classified as "low-risk," were followed over 2008-2010 for incident AF and stroke. Annualized incidence rates and risks were quantified for each combination of factors by using Cox regression. Annualized incidence rates for AF, stroke, and both were 3.59%, 3.27%, and 0.62% in 1 851 653 high-risk patients and 1.32%, 1.48%, and 0.18% in 1 156 221 low-risk patients, respectively. Among patients with 1 risk factor, those with age ≥75 had the highest hazards of incident AF and stroke (HR 9.2, 6.9). Among patients with 2 risk factors, those with age ≥75 and heart failure had the highest annualized incidence rates of AF and stroke (10.2%, 5.9%). The combination of age ≥75 and hypertension was prevalent and had the highest incidences of AF and stroke.Adults with combinations of known risk factors are at increased risk of incident AF and stroke, but combinations of risk factors are not always additive.

    View details for DOI 10.1161/JAHA.114.001723

    View details for Web of Science ID 000361489400008

    View details for PubMedID 26206736

    View details for PubMedCentralID PMC4608064

  • Does Age Influence Cardiac Resynchronization Therapy Use and Outcome? JACC. Heart failure Heidenreich, P. A., Tsai, V., Bao, H., Curtis, J., Goldstein, M., Curtis, L., Hernandez, A., Peterson, P., Turakhia, M. P., Masoudi, F. A. 2015; 3 (6): 497-504

    Abstract

    This study sought to describe the use of CRT-D and its association with survival for older patients.Many patients who receive cardiac resynchronization therapy with defibrillator (CRT-D) in practice are older than those included in clinical trials.We identified patients undergoing ICD implantation in the National Cardiovascular Disease Registry (NCDR) ICD registry from 2006 to 2009, who also met clinical trial criteria for CRT, including left ventricular ejection fraction (LVEF) ≤35%, QRS ≥120 ms, and New York Heart Association (NYHA) functional class III or IV. NCDR registry data were linked to the social security death index to determine the primary outcome of time to death from any cause. We identified 70,854 patients from 1,187 facilities who met prior trial criteria for CRT-D. The mean age of the 58,147 patients receiving CRT-D was 69.4 years with 6.4% of patients age 85 or older. CRT use was 80% or higher among candidates in all age groups. Follow-up was available for 42,285 patients age ≥65 years at 12 months.Receipt of CRT-D was associated with better survival at 1 year (82.1% vs. 77.1%, respectively) and 4 years (54.0% vs. 46.2% , respectively) than in those receiving only an ICD (p < 0.001). The CRT association with improved survival was not different for different age groups (p = 0.86 for interaction).More than 80% of older patients undergoing ICD implantation who were candidates for a CRT-D received the combined device. Mortality in older patients undergoing ICD implantation was high but was lower for those receiving CRT-D.

    View details for DOI 10.1016/j.jchf.2015.01.012

    View details for PubMedID 25982109

  • Feasibility of Extended Ambulatory Electrocardiogram Monitoring to Identify Silent Atrial Fibrillation in High-risk Patients: The Screening Study for Undiagnosed Atrial Fibrillation (STUDY-AF) CLINICAL CARDIOLOGY Turakhia, M. P., Ullal, A. J., Hoang, D. D., Than, C. T., Miller, J. D., Friday, K. J., Perez, M. V., Freeman, J. V., Wang, P. J., Heidenreich, P. A. 2015; 38 (5): 285-292

    Abstract

    Identification of silent atrial fibrillation (AF) could prevent stroke and other sequelae.Screening for AF using continuous ambulatory electrocardiographic (ECG) monitoring can detect silent AF in asymptomatic in patients with known risk factors.We performed a single-center prospective screening study using a wearable patch-based device that provides up to 2 weeks of continuous ambulatory ECG monitoring (iRhythm Technologies, Inc.). Inclusion criteria were age ≥55 years and ≥2 of the following risk factors: coronary disease, heart failure, hypertension, diabetes, sleep apnea. We excluded patients with prior AF, stroke, transient ischemic attack, implantable pacemaker or defibrillator, or with palpitations or syncope in the prior year.Out of 75 subjects (all male, age 69 ± 8.0 years; ejection fraction 57% ± 8.7%), AF was detected in 4 subjects (5.3%; AF burden 28% ± 48%). Atrial tachycardia (AT) was present in 67% (≥4 beats), 44% (≥8 beats), and 6.7% (≥60 seconds) of subjects. The combined diagnostic yield of sustained AT/AF was 11%. In subjects without sustained AT/AF, 11 (16%) had ≥30 supraventricular ectopic complexes per hour.Outpatient extended ECG screening for asymptomatic AF is feasible, with AF identified in 1 in 20 subjects and sustained AT/AF identified in 1 in 9 subjects, respectively. We also found a high prevalence of asymptomatic AT and frequent supraventricular ectopic complexes, which may be relevant to development of AF or stroke. If confirmed in a larger study, primary screening for AF could have a significant impact on public health.

    View details for DOI 10.1002/clc.22387

    View details for Web of Science ID 000354748000005

    View details for PubMedID 25873476

    View details for PubMedCentralID PMC4654330

  • EVIDENCE OF A GAP IN CARE: UTILIZATION OF RADIOLOGIC DIAGNOSTIC IMAGING IN PATIENTS WITH AND WITHOUT IMPLANTABLE DEFIBRILLATORS Nazarian, S., Reynolds, M. R., Ryan, M. P., Wolff, S. D., Mollenkopf, S., Turakhia, M. P. ELSEVIER SCIENCE INC. 2015: A47
  • Cardiovascular Disease Performance Measures in the Outpatient Setting in India: Insights From the American College of Cardiology's PINNACLE India Quality Improvement Program (PIQIP) JOURNAL OF THE AMERICAN HEART ASSOCIATION Kalra, A., Pokharel, Y., Hira, R. S., Risch, S., Vicera, V., Li, Q., Kalra, R. N., Kerkar, P. G., Kumar, G., Maddox, T. M., Oetgen, W. J., Glusenkamp, N., Turakhia, M. P., Virani, S. S. 2015; 4 (5)

    Abstract

    India has a growing burden of cardiovascular disease (CVD), yet data on the quality of outpatient care for patients with coronary artery disease, heart failure, and atrial fibrillation in India are very limited. We collected data on performance measures for 68 196 unique patients from 10 Indian cardiology outpatient departments from January 1, 2011, to February 5, 2014, in the American College of Cardiology's PINNACLE (Practice Innovation and Clinical Excellence) India Quality Improvement Program (PIQIP). PIQIP is India's first national outpatient CVD quality-improvement program.In the PIQIP registry, we estimated the prevalence of CVD risk factors (hypertension, diabetes, dyslipidemia, and current tobacco use) and CVD among outpatients. We examined adherence with performance measures established by the American College of Cardiology, the American Heart Association, and the American Medical Association Physician Consortium for Performance Improvement for coronary artery disease, heart failure, and atrial fibrillation. There were a total of 68 196 patients (155 953 patient encounters), with a mean age of 50.6 years (SD 18.2 years). Hypertension was present in 29.7% of patients, followed by diabetes (14.9%), current tobacco use (7.6%), and dyslipidemia (6.5%). Coronary artery disease was present in 14.8%, heart failure was noted in 4.0%, and atrial fibrillation was present in 0.5% of patients. Among eligible patients, the reported use of medications was as follows: aspirin in 48.6%, clopidogrel in 37.1%, and statin-based lipid-lowering therapy in 50.6% of patients with coronary artery disease; RAAS (renin-angiotensin-aldosterone system) antagonist in 61.9% and beta-blockers in 58.1% of patients with heart failure; and oral anticoagulants in 37.0% of patients with atrial fibrillation.This pilot study, initiated to improve outpatient CVD care in India, presents our preliminary results and barriers to data collection and demonstrates that such an initiative is feasible in a resource-limited environment. In addition, we attempted to outline areas for further improvement in outpatient CVD care delivery in India.

    View details for DOI 10.1161/JAHA.115.001910

    View details for Web of Science ID 000356347600018

    View details for PubMedID 25994444

  • Site-level variation in and practices associated with dabigatran adherence. JAMA Shore, S., Ho, P. M., Lambert-Kerzner, A., Glorioso, T. J., Carey, E. P., Cunningham, F., Longo, L., Jackevicius, C., Rose, A., Turakhia, M. P. 2015; 313 (14): 1443-1450

    Abstract

    Unlike warfarin, which requires routine laboratory testing and dose adjustment, target-specific oral anticoagulants like dabigatran do not. However, optimal follow-up infrastructure and modifiable site-level factors associated with improved adherence to dabigatran are unknown.To assess site-level variation in dabigatran adherence and to identify site-level practices associated with higher dabigatran adherence.Mixed-methods study involving retrospective quantitative and cross-sectional qualitative data. A total of 67 Veterans Health Administration sites with 20 or more patients filling dabigatran prescriptions between 2010 and 2012 for nonvalvular atrial fibrillation were sampled (4863 total patients; median, 51 patients per site). Forty-seven pharmacists from 41 eligible sites participated in the qualitative inquiry.Site-level practices identified included appropriate patient selection, pharmacist-driven patient education, and pharmacist-led adverse event and adherence monitoring.Dabigatran adherence (intensity of drug use during therapy) defined by proportion of days covered (ratio of days supplied by prescription to follow-up duration) of 80% or more.The median proportion of patients adherent to dabigatran was 74% (interquartile range [IQR], 66%-80%). After multivariable adjustment, dabigatran adherence across sites varied by a median odds ratio of 1.57. Review of practices across participating sites showed that appropriate patient selection was performed at 31 sites, pharmacist-led education was provided at 30 sites, and pharmacist-led monitoring at 28 sites. The proportion of adherent patients was higher at sites performing appropriate selection (75% vs 69%), education (76% vs 66%), and monitoring (77% vs 65%). Following multivariable adjustment, association between pharmacist-led education and dabigatran adherence was not statistically significant (relative risk [RR], 0.94; 95% CI, 0.83-1.06). Appropriate patient selection (RR, 1.14; 95% CI, 1.05-1.25), and provision of pharmacist-led monitoring (RR, 1.25; 95% CI, 1.11-1.41) were associated with better patient adherence. Additionally, longer duration of monitoring and providing more intensive care to nonadherent patients in collaboration with the clinician improved adherence.Among nonvalvular atrial fibrillation patients treated with dabigatran, there was variability in patient medication adherence across Veterans Health Administration sites. Specific pharmacist-based activities were associated with greater patient adherence to dabigatran.

    View details for DOI 10.1001/jama.2015.2761

    View details for PubMedID 25871670

  • Safety of ventricular tachycardia ablation in clinical practice: findings from 9699 hospital discharge records. Circulation. Arrhythmia and electrophysiology Katz, D. F., Turakhia, M. P., Sauer, W. H., Tzou, W. S., Heath, R. R., Zipse, M. M., Aleong, R. G., Varosy, P. D., Kao, D. P. 2015; 8 (2): 362-370

    Abstract

    Outcomes of ventricular tachycardia (VT) ablation have been described in clinical trials and single-center studies. We assessed the safety of VT ablation in clinical practice.Using administrative hospitalization data between 1994 and 2011, we identified hospitalizations with primary diagnosis of VT (International Classification of Diseases-9 Clinical Modification code: 427.1) and cardiac ablation (International Classification of Diseases-9 Clinical Modification code: 37.34). We quantified in-hospital adverse events (AEs), including death, stroke, intracerebral hemorrhage, pericardial complications, hematoma or hemorrhage, blood transfusion, or cardiogenic shock. Secondary outcomes included major AEs (stroke, tamponade, or death) and death. Multivariable mixed effects models identified patient and hospital characteristics associated with AEs. Of 9699 hospitalizations with VT ablations (age, 56.5±17.6; 60.1% men), AEs were reported in 825 (8.5%), major AEs in 295 (3.0%), and death in 110 (1.1%). Heart failure had the strongest association with death (odds ratio, 5.52; 95% confidence interval, 2.97-10.3) and major AE (odds ratio, 2.99; 95% confidence interval, 2.15-4.16). Anemia (odds ratio, 4.84; 95% confidence interval, 3.79-6.19) and unscheduled admission (odds ratio, 1.64; 95% confidence interval, 1.37-1.97) were associated with AEs. During the study period, incidence of AEs increased from 9.2% to 12.8% as did the burden of AE risk factors (0.034 patient/y; P<0.001). Hospital volume >25 cases/y was associated with fewer AEs compared with lower volume centers (6.4% versus 8.8%; P=0.008).VT ablation-associated AE rates in clinical practice are similar to those reported in the literature. Over time rates have increased as have the number of AE risk factors per patient. Ablations done electively and at hospitals with higher procedural volume are associated with lower incidence of AEs.

    View details for DOI 10.1161/CIRCEP.114.002336

    View details for PubMedID 25688143

  • Safety of Ventricular Tachycardia Ablation in Clinical Practice Findings from 9699 Hospital Discharge Records CIRCULATION-ARRHYTHMIA AND ELECTROPHYSIOLOGY Katz, D. F., Turakhia, M. P., Sauer, W. H., Tzou, W. S., Heath, R. R., Zipse, M. M., Aleong, R. G., Varosy, P. D., Kao, D. P. 2015; 8 (2): 362-U153

    Abstract

    Outcomes of ventricular tachycardia (VT) ablation have been described in clinical trials and single-center studies. We assessed the safety of VT ablation in clinical practice.Using administrative hospitalization data between 1994 and 2011, we identified hospitalizations with primary diagnosis of VT (International Classification of Diseases-9 Clinical Modification code: 427.1) and cardiac ablation (International Classification of Diseases-9 Clinical Modification code: 37.34). We quantified in-hospital adverse events (AEs), including death, stroke, intracerebral hemorrhage, pericardial complications, hematoma or hemorrhage, blood transfusion, or cardiogenic shock. Secondary outcomes included major AEs (stroke, tamponade, or death) and death. Multivariable mixed effects models identified patient and hospital characteristics associated with AEs. Of 9699 hospitalizations with VT ablations (age, 56.5±17.6; 60.1% men), AEs were reported in 825 (8.5%), major AEs in 295 (3.0%), and death in 110 (1.1%). Heart failure had the strongest association with death (odds ratio, 5.52; 95% confidence interval, 2.97-10.3) and major AE (odds ratio, 2.99; 95% confidence interval, 2.15-4.16). Anemia (odds ratio, 4.84; 95% confidence interval, 3.79-6.19) and unscheduled admission (odds ratio, 1.64; 95% confidence interval, 1.37-1.97) were associated with AEs. During the study period, incidence of AEs increased from 9.2% to 12.8% as did the burden of AE risk factors (0.034 patient/y; P<0.001). Hospital volume >25 cases/y was associated with fewer AEs compared with lower volume centers (6.4% versus 8.8%; P=0.008).VT ablation-associated AE rates in clinical practice are similar to those reported in the literature. Over time rates have increased as have the number of AE risk factors per patient. Ablations done electively and at hospitals with higher procedural volume are associated with lower incidence of AEs.

    View details for DOI 10.1161/CIRCEP.114.002336

    View details for Web of Science ID 000353309100018

    View details for PubMedID 25688143

  • ECONOMIC BURDEN OF UNDIAGNOSED NONVALVULAR ATRIAL FIBRILLATION IN THE UNITED STATES Turakhia, M., Shafrin, J., Bognar, K., Trocio, J., Abdulsattar, Y., Wiederkehr, D., Goldman, D. ELSEVIER SCIENCE INC. 2015: A475
  • COST VARIATION AND ASSOCIATED OUTCOMES OF CATHETER ABLATION FOR ATRIAL FIBRILLATION Perino, A., Fan, J., Schmitt, S., Chang, A. Y., Kaiser, D., Heidenreich, P., Swan, C., Narayan, S., Wang, P., Turakhia, M. ELSEVIER SCIENCE INC. 2015: A277
  • Correlates and outcomes of warfarin initiation in kidney transplant recipients newly diagnosed with atrial fibrillation. Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association Lenihan, C. R., Montez-Rath, M. E., Shen, J. I., Scandling, J. D., Turakhia, M. P., Chang, T. I., Winkelmayer, W. C. 2015; 30 (2): 321-329

    Abstract

    In the kidney transplant population with atrial fibrillation (AF), evidence regarding the effectiveness and safety of warfarin treatment is lacking. We used fee-for-service Medicare claims to identify kidney transplant recipients with newly diagnosed AF from the United States Renal Data System. Warfarin use within 30 days of AF diagnosis was ascertained from Medicare Part D prescription claims (2007-11) or using a validated algorithm (1997-2011). The study end points were (i) the composite of death, stroke or gastrointestinal bleed, (ii) death and (iii) death-censored graft failure. Warfarin user and non-user groups were balanced using inverse probability of treatment weighting and hazard ratios were (HRs) estimated using Cox regression. Among 718 subjects with an indication for anticoagulation, 24% initiated warfarin treatment within 30 days of AF diagnosis. Age was the only independent correlate of warfarin use [odds ratio = 1.02 per year; 95% confidence interval (95% CI) 1.01-1.04]. In the larger cohort of 6492 patients with AF, warfarin use [(23.5%) versus non-use (76.5%)] was associated with small and non-significant reductions in the composite of death, stroke or gastrointestinal bleed (HR = 0.92; 95% CI 0.83-1.02), death (HR = 0.92; 95% CI 0.82-1.02) and death-censored graft failure (HR = 0.90; 95% CI 0.76-1.08). Our study suggests the need for clinical trials of warfarin use in the kidney transplant population with AF.

    View details for DOI 10.1093/ndt/gfu323

    View details for PubMedID 25335507

  • Diagnostic yield of extenced cardiac patch monitoring in patients with stroke or TIA FRONTIERS IN NEUROLOGY Tung, C. E., Su, D., Turakhia, M. P., Lansberg, M. G. 2015; 5
  • Effectiveness of a community screening program for metabolic syndrome and cardiovascular risk factor identification in young South Asians adults. Diabetes & metabolic syndrome Prasad, M., Flowers, E., Mathur, A., Sridhar, V., Molina, C., Turakhia, M. 2015; 9 (1): 38-41

    Abstract

    Metabolic syndrome has been associated with increased risk of cardiovascular disease. We aimed to determine the effectiveness of a community-based screening program in identifying cardiovascular risk factors in healthy young South Asian population.Between 2006 and 2011, 3314 patients of all ages were recruited as a part of a prospective cohort study investigating cardiovascular risk in South Asians. We analyzed 1537 patients between the ages of 18 and 40. Demographic and baseline characteristics including baseline laboratory markers and blood pressures were obtained at initial visit.The total cohort of 1537 patients was 66.5% male, and the mean age was 35±5 years. Among participants who denied a history of hypercholesterolemia, 62% had elevated LDL-C (>100mg/dL), and 8% had markedly elevated LDL-C (>160mg/dL). Overall, diabetes was present in 4%, hypertension was present in 12% and hyperlipidemia was present in 46%. Low HDL-C (50% of men, 52% of women) and elevated triglycerides (44% of men, 18% of women) were the most prevalent components of metabolic syndrome. Metabolic syndrome was present in 14% of men and 8% of women and one-third (30%) of men and one-fifth (19%) of women had at least two component risk factors.This is the largest study to date assessing effectiveness of a community based screening program aiming to identify cardiovascular risk in young South Asians. We note significant modifiable risk at a young age. Such community based interventions can be effective at detecting and managing risk factors early in this vulnerable population.

    View details for DOI 10.1016/j.dsx.2014.04.025

    View details for PubMedID 25470638

  • Evaluating the Cost-effectiveness of Catheter Ablation of Atrial Fibrillation. Arrhythmia & electrophysiology review Chang, A. Y., Kaiser, D., Ullal, A., Perino, A. C., Heidenreich, P. A., Turakhia, M. P. 2014; 3 (3): 177-183

    Abstract

    Atrial fibrillation (AF) is one of the most common cardiac conditions treated in primary care and specialty cardiology settings, and is associated with considerable morbidity, mortality and cost. Catheter ablation, typically by electrically isolating the pulmonary veins and surrounding tissue, is more effective at maintaining sinus rhythm than conventional antiarrhythmic drug therapy and is now recommended as first-line therapy. From a value standpoint, the cost-effectiveness of ablation must incorporate the upfront procedural costs and risks with the benefits of longer term improvements in quality of life (QOL) and healthcare utilisation. Here, we present a primer on cost-effectiveness analysis (CEA), review the data on cost-effectiveness of AF ablation and outline key areas for further investigation.

    View details for DOI 10.15420/aer.2014.3.3.177

    View details for PubMedID 26835088

    View details for PubMedCentralID PMC4711535

  • Get With The Guidelines AFIB: novel quality improvement registry for hospitalized patients with atrial fibrillation. Circulation. Cardiovascular quality and outcomes Lewis, W. R., Piccini, J. P., Turakhia, M. P., Curtis, A. B., Fang, M., Suter, R. E., Page, R. L., Fonarow, G. C. 2014; 7 (5): 770-777

    Abstract

    Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. It is a cause of stroke, heart failure, and death. Guideline-based treatment can improve outcomes in AF. Unfortunately, adherence to these guidelines is low. Get With The Guidelines is a hospital-based performance initiative, which has been shown to improve adherence over time. Get With The Guidelines-AFIB is a novel quality improvement registry designed to improve adherence to AF guidelines.Hospitals will be recruited by regional American Heart Association staff and key stakeholders. Inpatients or observed patients with AF or atrial flutter will be enrolled. Data collected will include demographic, medical history, and clinical characteristics including laboratory values and treatments. Decision support will guide adherence to achievement and quality measures designed to improve adherence to anticoagulation, heart rate control, safe antiarrhythmic drug use, and patient education and follow-up. Increased adherence to guidelines will be facilitated using rapid-cycle quality improvement, site-specific reporting including national and regional benchmarks and hospital recognition for achievement. Primary analyses will include adherence to American Heart Association/American College of Cardiology performance measures and guidelines. Secondary analyses will include processes of care, risk stratification, treatment of special conditions or populations and use of particular treatment techniques.AF is common clinical problem with significant morbidity and mortality. Get With The Guidelines-AFIB is a national hospital-based AF quality improvement program designed to increase adherence to evidence-based guidelines for AF.

    View details for DOI 10.1161/CIRCOUTCOMES.114.001263

    View details for PubMedID 25185244

  • Association between success rate and citation count of studies of radiofrequency catheter ablation for atrial fibrillation: possible evidence of citation bias. Circulation. Cardiovascular quality and outcomes Perino, A. C., Hoang, D. D., Holmes, T. H., Santangeli, P., Heidenreich, P. A., Perez, M. V., Wang, P. J., Turakhia, M. P. 2014; 7 (5): 687-692

    Abstract

    The preferential citation of studies with the highest success rates could exaggerate perceived effectiveness, particularly for treatments with widely varying published success rates such as radiofrequency catheter ablation for atrial fibrillation.We systematically identified observational studies and clinical trials of radiofrequency catheter ablation of atrial fibrillation between 1990 and 2012. Generalized Poisson regression was used to estimate association between study success rate and total citation count, adjusting for sample size, journal impact factor, time since publication, study design, and whether first or last author was a consensus-defined pre-eminent expert. We identified 174 articles meeting our inclusion criteria (36 289 subjects). After adjustment only for time since publication, a 10-point increase above the mean in pooled reported success rates was associated with a 17.8% increase in citation count at 5 years postpublication (95% confidence interval, 7.1-28.4%; P<0.001). After additional adjustment for impact factor, sample size, randomized trial design, and pre-eminent expert authorship, the association remained significant (18.6% increase in citation count; 95% confidence interval, 7.6-29.6%; P<0.0001). In this full model, time since publication, impact factor, and pre-eminent expert authorship were significant covariates, whereas randomized control trial design and study sample size were not.Among studies of radiofrequency catheter ablation of atrial fibrillation, high success rate was independently associated with citation count, which may indicate citation bias. To readers of the literature, radiofrequency catheter ablation of atrial fibrillation could be perceived to be more effective than the data supports. These findings may have implications for a wide variety of novel cardiovascular therapies.

    View details for DOI 10.1161/CIRCOUTCOMES.114.000912

    View details for PubMedID 25205786

  • Get With The Guidelines AFIB Novel Quality Improvement Registry for Hospitalized Patients With Atrial Fibrillation CIRCULATION-CARDIOVASCULAR QUALITY AND OUTCOMES Lewis, W. R., Piccini, J. P., Turakhia, M. P., Curtis, A. B., Fang, M., Suter, R. E., Page, R. L., Fonarow, G. C. 2014; 7 (5): 770-777

    Abstract

    Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. It is a cause of stroke, heart failure, and death. Guideline-based treatment can improve outcomes in AF. Unfortunately, adherence to these guidelines is low. Get With The Guidelines is a hospital-based performance initiative, which has been shown to improve adherence over time. Get With The Guidelines-AFIB is a novel quality improvement registry designed to improve adherence to AF guidelines.Hospitals will be recruited by regional American Heart Association staff and key stakeholders. Inpatients or observed patients with AF or atrial flutter will be enrolled. Data collected will include demographic, medical history, and clinical characteristics including laboratory values and treatments. Decision support will guide adherence to achievement and quality measures designed to improve adherence to anticoagulation, heart rate control, safe antiarrhythmic drug use, and patient education and follow-up. Increased adherence to guidelines will be facilitated using rapid-cycle quality improvement, site-specific reporting including national and regional benchmarks and hospital recognition for achievement. Primary analyses will include adherence to American Heart Association/American College of Cardiology performance measures and guidelines. Secondary analyses will include processes of care, risk stratification, treatment of special conditions or populations and use of particular treatment techniques.AF is common clinical problem with significant morbidity and mortality. Get With The Guidelines-AFIB is a national hospital-based AF quality improvement program designed to increase adherence to evidence-based guidelines for AF.

    View details for DOI 10.1161/CIRCOUTCOMES.114.001263

    View details for Web of Science ID 000342365200022

  • Association Between Success Rate and Citation Count of Studies of Radiofrequency Catheter Ablation for Atrial Fibrillation Possible Evidence of Citation Bias CIRCULATION-CARDIOVASCULAR QUALITY AND OUTCOMES Perino, A. C., Hoang, D. D., Holmes, T. H., Santangeli, P., Heidenreich, P. A., Perez, M. V., Wang, P. J., Turakhia, M. P. 2014; 7 (5): 687-692

    Abstract

    The preferential citation of studies with the highest success rates could exaggerate perceived effectiveness, particularly for treatments with widely varying published success rates such as radiofrequency catheter ablation for atrial fibrillation.We systematically identified observational studies and clinical trials of radiofrequency catheter ablation of atrial fibrillation between 1990 and 2012. Generalized Poisson regression was used to estimate association between study success rate and total citation count, adjusting for sample size, journal impact factor, time since publication, study design, and whether first or last author was a consensus-defined pre-eminent expert. We identified 174 articles meeting our inclusion criteria (36 289 subjects). After adjustment only for time since publication, a 10-point increase above the mean in pooled reported success rates was associated with a 17.8% increase in citation count at 5 years postpublication (95% confidence interval, 7.1-28.4%; P<0.001). After additional adjustment for impact factor, sample size, randomized trial design, and pre-eminent expert authorship, the association remained significant (18.6% increase in citation count; 95% confidence interval, 7.6-29.6%; P<0.0001). In this full model, time since publication, impact factor, and pre-eminent expert authorship were significant covariates, whereas randomized control trial design and study sample size were not.Among studies of radiofrequency catheter ablation of atrial fibrillation, high success rate was independently associated with citation count, which may indicate citation bias. To readers of the literature, radiofrequency catheter ablation of atrial fibrillation could be perceived to be more effective than the data supports. These findings may have implications for a wide variety of novel cardiovascular therapies.

    View details for DOI 10.1161/CIRCOUTCOMES.114.000912

    View details for Web of Science ID 000342365200011

  • Increased Mortality Associated With Digoxin in Contemporary Patients With Atrial Fibrillation: Findings From the TREAT-AF Study. Journal of the American College of Cardiology Turakhia, M. P., Santangeli, P., Winkelmayer, W. C., Xu, X., Ullal, A. J., Than, C. T., Schmitt, S., Holmes, T. H., Frayne, S. M., Phibbs, C. S., Yang, F., Hoang, D. D., Ho, P. M., Heidenreich, P. A. 2014; 64 (7): 660-668

    Abstract

    Despite endorsement of digoxin in clinical practice guidelines, there exist limited data on its safety in atrial fibrillation/flutter (AF).The goal of this study was to evaluate the association of digoxin with mortality in AF.Using complete data of the TREAT-AF (The Retrospective Evaluation and Assessment of Therapies in AF) study from the U.S. Department of Veterans Affairs (VA) healthcare system, we identified patients with newly diagnosed, nonvalvular AF seen within 90 days in an outpatient setting between VA fiscal years 2004 and 2008. We used multivariate and propensity-matched Cox proportional hazards to evaluate the association of digoxin use with death. Residual confounding was assessed by sensitivity analysis.Of 122,465 patients with 353,168 person-years of follow-up (age 72.1 ± 10.3 years, 98.4% male), 28,679 (23.4%) patients received digoxin. Cumulative mortality rates were higher for digoxin-treated patients than for untreated patients (95 vs. 67 per 1,000 person-years; p < 0.001). Digoxin use was independently associated with mortality after multivariate adjustment (hazard ratio [HR]: 1.26, 95% confidence interval [CI]: 1.23 to 1.29, p < 0.001) and propensity matching (HR: 1.21, 95% CI: 1.17 to 1.25, p < 0.001), even after adjustment for drug adherence. The risk of death was not modified by age, sex, heart failure, kidney function, or concomitant use of beta-blockers, amiodarone, or warfarin.Digoxin was associated with increased risk of death in patients with newly diagnosed AF, independent of drug adherence, kidney function, cardiovascular comorbidities, and concomitant therapies. These findings challenge current cardiovascular society recommendations on use of digoxin in AF.

    View details for DOI 10.1016/j.jacc.2014.03.060

    View details for PubMedID 25125296

    View details for PubMedCentralID PMC4405246

  • Adherence to dabigatran therapy and longitudinal patient outcomes: Insights from the Veterans Health Administration AMERICAN HEART JOURNAL Shore, S., Carey, E. P., Turakhia, M. P., Jackevicius, C. A., Cunningham, F., Pilote, L., Bradley, S. M., Maddox, T. M., Grunwald, G. K., Baron, A. E., Rumsfeld, J. S., Varosy, P. D., Schneider, P. M., Marzec, L. N., Ho, P. M. 2014; 167 (6): 810-817

    Abstract

    Dabigatran is a novel oral anti-coagulant (NOAC) that reduces risk of stroke in patients with non-valvular atrial fibrillation (NVAF). It does not require routine monitoring with laboratory testing which may have an adverse impact on adherence. We aimed to describe adherence to dabigatran in the first year after initiation and assess the association between non-adherence to dabigatran and clinical outcomes in a large integrated healthcare system.We studied a national cohort of 5,376 patients with NVAF, initiated on dabigatran between October-2010 and September-2012 at all Veterans Affairs hospitals. Adherence to dabigatran was calculated as proportion of days covered (PDC) and association between PDC and outcomes was assessed using standard regression techniques.Mean age of the study cohort was 71.3 ± 9.7 years; 98.3% were men and mean CHADS2 score was 2.4 ± 1.2 (mean CHA2DS2VASc score 3.2 ± 1.4). Median PDC was 94% (IQR 76%-100%; mean PDC 84% ± 22%) over a median follow-up of 244 days (IQR 140-351). A total of 1,494 (27.8%) patients had a PDC <80% and were classified as non-adherent. After multivariable adjustment, lower adherence was associated with increased risk for combined all-cause mortality and stroke (HR 1.13, 95% CI 1.07-1.19 per 10% decrease in PDC). Adherence to dabigatran was not associated with non-fatal bleeding or myocardial infarction.In the year after initiation, adherence to dabigatran for a majority of patients is very good. However, 28% of patients in our cohort had poor adherence. Furthermore, lower adherence to dabigatran was associated with increased adverse outcomes. Concerted efforts are needed to optimize adherence to NOACs.

    View details for DOI 10.1016/j.ahj.2014.03.023

    View details for Web of Science ID 000338350800009

    View details for PubMedID 24890529

  • Relation of Left Atrial Dysfunction to Ischemic Stroke in Patients With Coronary Heart Disease (from the Heart and Soul Study). American journal of cardiology Wong, J. M., Welles, C. C., Azarbal, F., Whooley, M. A., Schiller, N. B., Turakhia, M. P. 2014; 113 (10): 1679-1684

    Abstract

    This study sought to determine whether left atrial (LA) dysfunction independently predicts ischemic stroke. Atrial fibrillation (AF) impairs LA function and is associated with ischemic stroke. However, ischemic stroke frequently occurs in patients without known AF. The direct relation between LA function and risk of ischemic stroke is unknown. We performed transthoracic echocardiography at rest in 983 subjects with stable coronary heart disease. To quantify LA dysfunction, we used the left atrial function index (LAFI), a validated formula incorporating LA volumes at end-atrial systole and diastole. Cox proportional hazards models were used to evaluate the association between LAFI and ischemic stroke or transient ischemic attack (TIA). Over a mean follow-up of 7.1 years, 58 study participants (5.9%) experienced an ischemic stroke or TIA. In patients without known baseline AF or warfarin therapy (n = 893), participants in the lowest quintile of LAFI had >3 times the risk of ischemic stroke or TIA (hazard ratio 3.3, 95% confidence interval 1.1 to 9.7, p = 0.03) compared with those in the highest quintile. For each standard deviation (18.8 U) decrease in LAFI, the hazard of ischemic stroke or TIA increased by 50% (hazard ratio 1.5, 95% confidence interval 1.0 to 2.1, p = 0.04). Among measured echocardiographic indexes of LA function, including LA volume, LAFI was the strongest predictor of ischemic stroke or TIA. In conclusion, LA dysfunction is an independent risk factor for stroke or TIA, even in patients without baseline AF.

    View details for DOI 10.1016/j.amjcard.2014.02.021

    View details for PubMedID 24792737

  • Association of CHADS2, CHA2DS2-VASc, and R2CHADS2 Scores With Left Atrial Dysfunction in Patients With Coronary Heart Disease (from the Heart and Soul Study). American journal of cardiology Azarbal, F., Welles, C. C., Wong, J. M., Whooley, M. A., Schiller, N. B., Turakhia, M. P. 2014; 113 (7): 1166-1172

    Abstract

    The predictive ability of the CHADS2 index to stratify stroke risk may be mechanistically linked to severity of left atrial (LA) dysfunction. This study investigated the association between the CHADS2 score and LA function. We performed resting transthoracic echocardiography in 970 patients with stable coronary heart disease and normal ejection fraction and calculated baseline LA functional index (LAFI) using a validated formula: (LA emptying fraction×left ventricular outflow tract velocity time integral)/LA end-systolic volume indexed to body surface area. We performed regression analyses to evaluate the association between risk scores and LAFI. Among 970 subjects, mean CHADS2 was 1.7±1.2. Mean LAFI decreased across tertiles of CHADS2 (42.8±18.1, 37.8±19.1, 36.7±19.4, p<0.001). After adjustment for age, sex, race, systolic blood pressure, hyperlipidemia, myocardial infarction, revascularization, body mass index, smoking, and alcohol use, high CHADS2 remained associated with the lowest quartile of LAFI (odds ratio 2.34, p=0.001). In multivariable analysis of component co-morbidities, heart failure, age, and creatinine clearance<60 ml/min were strongly associated with LA dysfunction. For every point increase in CHADS2, the LAFI decreased by 4.0%. Secondary analyses using CHA2DS2-VASc and R2CHADS2 scores replicated these results. Findings were consistent when excluding patients with baseline atrial fibrillation. In conclusion, CHADS2, CHA2DS2-VASc, and R2CHADS2 scores are associated with LA dysfunction, even in patients without baseline atrial fibrillation. These findings merit further study to determine the role of LA dysfunction in cardioembolic stroke and the value of LAFI for risk stratification.

    View details for DOI 10.1016/j.amjcard.2013.12.028

    View details for PubMedID 24507169

  • Warfarin treatment in patients with atrial fibrillation and advanced chronic kidney disease: sins of omission or commission? JAMA Winkelmayer, W. C., Turakhia, M. P. 2014; 311 (9): 913-915

    View details for DOI 10.1001/jama.2014.1781

    View details for PubMedID 24595773

  • Phenytoin toxicity unlikely to result in arrhythmias-reply. JAMA internal medicine Johnson, C. J., Turakhia, M. P. 2014; 174 (1): 167-168

    View details for DOI 10.1001/jamainternmed.2013.11168

    View details for PubMedID 24394935

  • Regarding "feasibility and safety of same-day discharge after implantable cardioverter defibrillator placement for primary prevention". Pacing and clinical electrophysiology : PACE Turakhia, M. P., Holmes, T. 2014; 37 (1): 131-?

    View details for DOI 10.1111/pace.12273

    View details for PubMedID 24033450

  • Diagnostic Yield of Extended Cardiac Patch Monitoring in Patients with Stroke or TIA. Frontiers in neurology Tung, C. E., Su, D., Turakhia, M. P., Lansberg, M. G. 2014; 5: 266-?

    Abstract

    It is important to evaluate patients with transient ischemic attack (TIA) or stroke for atrial fibrillation (AF) because the detection of AF changes the recommended anti-thrombotic regimen from treatment with an antiplatelet agent to oral anticoagulation. This study describes the diagnostic yield of a patch-based, single-use, and water-resistant 14-day continuous cardiac rhythm monitor (ZIO Patch) in patients with stroke or TIA.We obtained data from the manufacturer and servicer of the ZIO Patch (iRhythm Technologies). Patients who were monitored between January 2012 and June 2013 and whose indication for monitoring was TIA or stroke were included. The duration of monitoring, the number and type of arrhythmias, and the time to first arrhythmia were documented.One thousand one hundred seventy-one monitoring reports were analyzed. The mean monitor wear time was 10.9 days and the median wear time was 13.0 days (interquartile range 7.2-14.0). The median analyzable time relative to the total wear time was 98.7% (IQR 96.0-99.5%). AF was present in 5.0% of all reports. The mean duration before the first episode of paroxysmal AF (PAF) was 1.5 days and the median duration was 0.4 days. 14.3% of first PAF episodes occurred after 48 h. The mean PAF burden was 12.7% of the total monitoring duration.Excellent quality of the recordings and very good patient compliance coupled with a substantial proportion of AF detection beyond the first 48 h of monitoring suggest that the cardiac patch is superior to conventional 48-h Holter monitors for AF detection in patients with stroke or TIA.

    View details for DOI 10.3389/fneur.2014.00266

    View details for PubMedID 25628595

    View details for PubMedCentralID PMC4290477

  • Adherence and persistence in the use of warfarin after hospital discharge among patients with heart failure and atrial fibrillation. Journal of cardiac failure Eapen, Z. J., Mi, X., Qualls, L. G., Hammill, B. G., Fonarow, G. C., Turakhia, M. P., Heidenreich, P. A., Peterson, E. D., Curtis, L. H., Hernandez, A. F., Al-Khatib, S. M. 2014; 20 (1): 23-30

    Abstract

    Postdischarge adherence and long-term persistence in the use of warfarin among patients with heart failure and atrial fibrillation without contraindications have not been fully described.We identified patients with heart failure and atrial fibrillation who were ≥65 years old, eligible for warfarin, and discharged home from hospitals in the Get With the Guidelines-Heart Failure registry from January 1, 2006, to December 31, 2009. We used linked Medicare prescription drug event data to measure adherence and persistence. The main outcome measures were rates of prescription at discharge, outpatient dispensing, discontinuation, and adherence as measured by the medication possession ratio. We hypothesized that adherence to warfarin would differ according to whether patients received the prescription at discharge. Among 2,691 eligible patients, 1,856 (69.0%) were prescribed warfarin at discharge. Patients prescribed warfarin at discharge had significantly higher prescription fill rates within 90 days (84.5% vs 12.3%; P < .001) and 1 year (91.6% vs 16.8%; P < .001) and significantly higher medication possession ratios (0.78 vs 0.63; P < .001). Among both previous nonusers and existing users, fill rates at 90 days and 1 year and possession ratios were significantly higher among those prescribed warfarin at discharge.One-third of eligible patients with heart failure and atrial fibrillation were not prescribed warfarin at discharge from a heart failure hospitalization, and few started therapy as outpatients. In contrast, most patients who were prescribed warfarin at discharge filled the prescription within 90 days and remained on therapy at 1 year.

    View details for DOI 10.1016/j.cardfail.2013.11.006

    View details for PubMedID 24275703

  • Clinical reminders to providers of patients with reduced left ventricular ejection fraction increase defibrillator referral: a randomized trial. Circulation. Heart failure Gupta, A., Gholami, P., Turakhia, M. P., Friday, K., Heidenreich, P. A. 2014; 7 (1): 140-145

    Abstract

    Background- Many patients who are candidates for implantable cardioverter defibrillators (ICDs) are not referred for potential implantation. We sought to determine if a simple provider reminder would increase referrals. Methods and Results- We identified consecutive patients from January 2007 through July 2010 in the VA Palo Alto Health Care System with a left ventricular ejection fraction <35% on echocardiography. Patients were excluded using available administrative data only (no chart review) if they were known to have an ICD, if they were ≥80 years old, or if they did not have a current primary care or cardiology provider within the system. We randomized patients to no intervention or a clinical note to the provider in the medical record. The outcomes were referral for consideration of defibrillator implantation (primary) and documented discussion (secondary). Of 330 patients with left ventricular ejection fraction ≤35%, 128 were known to have an ICD, 85 were no longer followed in the healthcare system, and 28 were ≥80 years old, leaving 89 patients to be randomized. Forty-six patients were randomized to intervention and 43 to control. Eleven of 46 (24%) intervention patients were referred for consideration of ICD implantation during the following 6 months versus 1 of 43 (2%) control patients (P=0.004). Overall, 31 of 46 (67%) intervention patients versus 19 of 43 (44%) control patients had documentation discussing potential candidacy for defibrillators (P=0.05). Conclusions- In patients with low left ventricular ejection fraction, a simple electronic medical record-based intervention directed to their providers improved the rates of referral for ICD implantation. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT01217827.

    View details for DOI 10.1161/CIRCHEARTFAILURE.113.000753

    View details for PubMedID 24319096

  • Patterns of Adherence to Dabigatran and its Association With Outcomes Shore, S., Carev, E. P., Turakhia, M., Jackevicius, C., Cunnigham, F., Baron, A. E., Grunwald, G. K., Pilote, L., Bradley, S. M., Maddox, T. M., Rumsfeld, J., Varosy, P. D., Ho, P. LIPPINCOTT WILLIAMS & WILKINS. 2013
  • Citation Bias Favoring Studies With Higher Success Rates for Catheter Ablation of Atrial Fibrillation Perino, A. C., Hoang, D. D., Holmes, T. H., Santangeli, P., Turakhia, M. P. LIPPINCOTT WILLIAMS & WILKINS. 2013
  • Adherence With Dabigatran Therapy in Patients With Atrial Fibrillation Jackevicius, C., Avgil, M., Tu, J., Essebag, V., Eisenberg, M., Atzema, C., Ho, M., Turakhia, M., Lu, L., Behlouli, H., Pilote, L. LIPPINCOTT WILLIAMS & WILKINS. 2013
  • Burden, timing, and relationship of cardiovascular hospitalization to mortality among Medicare beneficiaries with newly diagnosed atrial fibrillation. American heart journal Turakhia, M. P., Solomon, M. D., Jhaveri, M., Davis, P., Eber, M. R., Conrad, R., Summers, N., Lakdawalla, D. 2013; 166 (3): 573-580

    Abstract

    Limited data exist on the burden and relationship of cardiovascular (CV) hospitalization to mortality after newly diagnosed with atrial fibrillation (AF).Using a 20% sample of nationwide Medicare Part A and B claims data, we performed a retrospective cohort study of Medicare beneficiaries with newly diagnosed AF (2004-2008). Cox proportional hazards time-varying exposures were used to determine the risk of death among patients with CV hospitalization after AF diagnosis.Of 228,295 patients (mean age 79.6 ± 7.4 years, 56% female), 57% had a CV hospitalization after diagnosis of AF (41% in the first year). The most common primary CV hospitalization diagnoses were AF/supraventricular arrhythmias (21%), heart failure (19%), myocardial infarction (11%), and stroke/transient ischemic attack (7.7%). Incidence rates per 1,000 person-years among patients with and without CV hospitalization were 114 and 87, respectively, for all-cause mortality. After adjustment for covariates and time to CV hospitalization, the hazard of mortality among newly diagnosed AF patients with CV hospitalization, compared with those without CV hospitalization, was higher (hazard ratio 1.22, 95% CI 1.20-1.24).Cardiovascular hospitalization is common in the first year after AF diagnosis. Atrial fibrillation, heart failure, myocardial infarction, and stroke/transient ischemic attack account for half of primary hospitalization diagnosis. Cardiovascular hospitalization is independently associated with mortality, irrespective of time from diagnosis to first hospitalization, and represents a critical inflection point in survival trajectory. These findings highlight the importance of CV hospitalization as a marker of disease progression and poor outcomes. Efforts to clarify the determinants of hospitalization could inform interventions to reduce admissions and improve survival.

    View details for DOI 10.1016/j.ahj.2013.07.003

    View details for PubMedID 24016509

  • Diagnostic utility of a novel leadless arrhythmia monitoring device. American journal of cardiology Turakhia, M. P., Hoang, D. D., Zimetbaum, P., Miller, J. D., Froelicher, V. F., Kumar, U. N., Xu, X., Yang, F., Heidenreich, P. A. 2013; 112 (4): 520-524

    Abstract

    Although extending the duration of ambulatory electrocardiographic monitoring beyond 24 to 48 hours can improve the detection of arrhythmias, lead-based (Holter) monitors might be limited by patient compliance and other factors. We, therefore, evaluated compliance, analyzable signal time, interval to arrhythmia detection, and diagnostic yield of the Zio Patch, a novel leadless, electrocardiographic monitoring device in 26,751 consecutive patients. The mean wear time was 7.6 ± 3.6 days, and the median analyzable time was 99% of the total wear time. Among the patients with detected arrhythmias (60.3% of all patients), 29.9% had their first arrhythmia and 51.1% had their first symptom-triggered arrhythmia occur after the initial 48-hour period. Compared with the first 48 hours of monitoring, the overall diagnostic yield was greater when data from the entire Zio Patch wear duration were included for any arrhythmia (62.2% vs 43.9%, p <0.0001) and for any symptomatic arrhythmia (9.7% vs 4.4%, p <0.0001). For paroxysmal atrial fibrillation (AF), the mean interval to the first detection of AF was inversely proportional to the total AF burden, with an increasing proportion occurring after 48 hours (11.2%, 10.5%, 20.8%, and 38.0% for an AF burden of 51% to 75%, 26% to 50%, 1% to 25%, and <1%, respectively). In conclusion, extended monitoring with the Zio Patch for ≤14 days is feasible, with high patient compliance, a high analyzable signal time, and an incremental diagnostic yield beyond 48 hours for all arrhythmia types. These findings could have significant implications for device selection, monitoring duration, and care pathways for arrhythmia evaluation and AF surveillance.

    View details for DOI 10.1016/j.amjcard.2013.04.017

    View details for PubMedID 23672988

  • Outcomes after kidney transplantation of patients previously diagnosed with atrial fibrillation. American journal of transplantation Lenihan, C. R., Montez-Rath, M. E., Scandling, J. D., Turakhia, M. P., Winkelmayer, W. C. 2013; 13 (6): 1566-1575

    Abstract

    Little is known about the prevalence and outcomes of patients with atrial fibrillation/flutter (AF) who receive a kidney transplant. We identified all patients who had >1 year of uninterrupted Medicare A+B coverage before receiving their first kidney transplant (1997-2009). The presence of pretransplant AF was ascertained from diagnosis codes in Medicare physician claims. We studied the posttransplant outcomes of death, all-cause graft failure, death-censored graft failure and stroke using multivariable Cox regression. Of 62 706 eligible first kidney transplant recipients studied, 3794 (6.4%) were diagnosed with AF prior to kidney transplant. Over a mean follow up of 4.9 years, 40.6% of AF patients and 24.9% without AF died. All-cause and death-censored graft failure were 46.8% and 16.5%, respectively, in the AF group and 36.4% and 19.5%, respectively, in those without AF. Ischemic stroke occurred in 2.8% of patients with and 1.6% of patients without AF. In patients with AF, multivariable-adjusted hazard ratios (95% confidence intervals) for death, graft failure, death-censored graft failure and ischemic stroke were 1.46 (1.38-1.54), 1.41 (1.34-1.48), 1.26 (1.15-1.37) and 1.36 (1.10-1.68), respectively. Pre-existing AF is associated with poor posttransplant outcomes. Special attention should be paid to AF in pretransplant evaluation, counseling and risk stratification of kidney transplant candidates.

    View details for DOI 10.1111/ajt.12197

    View details for PubMedID 23721555

  • Comparative effectiveness of antiarrhythmic drugs on cardiovascular hospitalization and mortality in atrial fibrillation JOURNAL OF COMPARATIVE EFFECTIVENESS RESEARCH Lakdawalla, D., Turakhia, M. P., Jhaveri, M., Mozaffari, E., Davis, P., Bradley, L., Solomon, M. D. 2013; 2 (3): 301-312

    Abstract

    To assess, through a systematic review, evidence for the effects of antiarrhythmic drugs (AADs) on cardiovascular (CV) hospitalization and mortality.English language articles were identified using MEDLINE, EMBASE and the Cochrane Clinical Trial Registry and were screened for study applicability and methodological quality.Out of 3526 identified studies, 38 were selected for analysis (19 evaluated individual AADs, 13 compared rate- versus rhythm-control strategies, and 6 evaluated multiple AADs but did not report outcomes for individual agents). None of the studies examining individual AADs employed the CV hospitalization end point used in ATHENA (the reference trial). There were no head-to-head comparisons of individual AADs on CV hospitalization. Most high-quality studies used multidrug rate- versus rhythm-control strategies.Assessment of the comparative effectiveness of individual AADs on CV hospitalization and mortality end points is not possible with the current evidence.

    View details for DOI 10.2217/CER.13.19

    View details for Web of Science ID 000319022800018

  • IDENTIFICATION OF PATIENTS AT HIGH RISK FOR SUBSEQUENT DEVELOPMENT OF ATRIAL FIBRILLATION OR STROKE USING A CLAIMS DATABASE Reynolds, M. R., Hunter, T. D., Mollenkopf, S. A., Turakhia, M. P. ELSEVIER SCIENCE INC. 2013: A25–A26
  • SLEEP DISORDERED BREATHING AND CARDIOVASCULAR RISK IN OLDER PATIENTS INITIATING DIALYSIS Tuohy, C., Montez-Rath, M. E., Turakhia, M., Chang, T. I., Winkelmayer, W. C. W B SAUNDERS CO-ELSEVIER INC. 2013: A95
  • US Health Care Policy and Reform: implications for cardiac electrophysiology JOURNAL OF INTERVENTIONAL CARDIAC ELECTROPHYSIOLOGY Turakhia, M. P., Ullal, A. J. 2013; 36 (2): 129-136

    Abstract

    In response to unsustainably rising costs, variable quality and access to health care, and the projected insolvency of vital safety net insurance programs, the federal government has proposed important health policy and regulatory changes in the USA. The US Supreme Court's decision to uphold most of the major provisions of the Affordable Care Act will lead to some of the most sweeping government reforms on entitlements since the creation of Medicare. Furthermore, implementation of new organizational, reimbursement, and health care delivery models will strongly affect the practice of cardiac electrophysiology. In this brief review, we will provide background and context to the problem of rising health care costs and describe salient reforms and their projected impacts on the field and practice of cardiac electrophysiology.

    View details for DOI 10.1007/s10840-012-9773-3

    View details for Web of Science ID 000316749200005

    View details for PubMedID 23397248

  • Foreword: health policy and cardiac electrophysiology JOURNAL OF INTERVENTIONAL CARDIAC ELECTROPHYSIOLOGY Hlatky, M. A., Reynolds, M., Turakhia, M. 2013; 36 (2): 97-97

    View details for DOI 10.1007/s10840-013-9789-3

    View details for Web of Science ID 000316749200001

    View details for PubMedID 23479090

  • Bizarre and Wide QRS After Liver Transplant. JAMA internal medicine Johnson, C. J., Scheinman, M. A., Turakhia, M. P. 2013: 1

    View details for DOI 10.1001/jamainternmed.2013.644a

    View details for PubMedID 23609165

  • Differences and trends in stroke prevention anticoagulation in primary care vs cardiology specialty management of new atrial fibrillation: The Retrospective Evaluation and Assessment of Therapies in AF (TREAT-AF) study AMERICAN HEART JOURNAL Turakhia, M. P., Hoang, D. D., Xu, X., Frayne, S., Schmitt, S., Yang, F., Phibbs, C. S., Than, C. T., Wang, P. J., Heidenreich, P. A. 2013; 165 (1): 93-?

    Abstract

    Atrial fibrillation and flutter (AF, collectively) cause stroke. We evaluated whether treating specialty influences warfarin prescription in patients with newly diagnosed AF.In the TREAT-AF study, we used Veterans Health Administration health record and claims data to identify patients with newly diagnosed AF between October 2004 and November 2008 and at least 1 internal medicine/primary care or cardiology outpatient encounter within 90 days after diagnosis. The primary outcome was prescription of warfarin.In 141,642 patients meeting the inclusion criteria, the mean age was 72.3 ± 10.2 years, 1.48% were women, and 25.8% had cardiology outpatient care. Cardiology-treated patients had more comorbidities and higher mean CHADS2 scores (1.8 vs 1.6, P < .0001). Warfarin use was higher in cardiology-treated vs primary care only-treated patients (68.6% vs 48.9%, P < .0001). After covariate and site-level adjustment, cardiology care was significantly associated with warfarin use (odds ratio [OR] 2.05, 95% CI 1.99-2.11). These findings were consistent across a series of adjusted models (OR 2.05-2.20), propensity matching (OR 1.98), and subgroup analyses (OR 1.58-2.11). Warfarin use in primary-care-only patients declined from 2004 to 2008 (51.6%-44.0%, P < .0001), whereas the adjusted odds of warfarin receipt with cardiology care (vs primary care) increased from 2004 to 2008 (1.88-2.24, P < .0001).In patients with newly diagnosed AF, we found large differences in anticoagulation use by treating specialty. A divergent 5-year trend of risk-adjusted warfarin use was observed. Treating specialty influences stroke prevention care and may impact clinical outcomes.

    View details for DOI 10.1016/j.ahj.2012.10.010

    View details for Web of Science ID 000312272900017

    View details for PubMedID 23237139

  • Differences and trends in stroke prevention anticoagulation in primary care vs cardiology specialty management of new atrial fibrillation: The Retrospective Evaluation and Assessment of Therapies in AF (TREAT-AF) study. American heart journal Turakhia, M. P., Hoang, D. D., Xu, X., Frayne, S., Schmitt, S., Yang, F., Phibbs, C. S., Than, C. T., Wang, P. J., Heidenreich, P. A. 2013; 165 (1): 93-101 e1

    Abstract

    Atrial fibrillation and flutter (AF, collectively) cause stroke. We evaluated whether treating specialty influences warfarin prescription in patients with newly diagnosed AF.In the TREAT-AF study, we used Veterans Health Administration health record and claims data to identify patients with newly diagnosed AF between October 2004 and November 2008 and at least 1 internal medicine/primary care or cardiology outpatient encounter within 90 days after diagnosis. The primary outcome was prescription of warfarin.In 141,642 patients meeting the inclusion criteria, the mean age was 72.3 ± 10.2 years, 1.48% were women, and 25.8% had cardiology outpatient care. Cardiology-treated patients had more comorbidities and higher mean CHADS2 scores (1.8 vs 1.6, P < .0001). Warfarin use was higher in cardiology-treated vs primary care only-treated patients (68.6% vs 48.9%, P < .0001). After covariate and site-level adjustment, cardiology care was significantly associated with warfarin use (odds ratio [OR] 2.05, 95% CI 1.99-2.11). These findings were consistent across a series of adjusted models (OR 2.05-2.20), propensity matching (OR 1.98), and subgroup analyses (OR 1.58-2.11). Warfarin use in primary-care-only patients declined from 2004 to 2008 (51.6%-44.0%, P < .0001), whereas the adjusted odds of warfarin receipt with cardiology care (vs primary care) increased from 2004 to 2008 (1.88-2.24, P < .0001).In patients with newly diagnosed AF, we found large differences in anticoagulation use by treating specialty. A divergent 5-year trend of risk-adjusted warfarin use was observed. Treating specialty influences stroke prevention care and may impact clinical outcomes.

    View details for DOI 10.1016/j.ahj.2012.10.010

    View details for PubMedID 23237139

  • Oral Antithrombotic Agents for the Prevention of Stroke in Nonvalvular Atrial Fibrillation A Science Advisory for Healthcare Professionals From the American Heart Association/American Stroke Association STROKE Furie, K. L., Goldstein, L. B., Albers, G. W., Khatri, P., Neyens, R., Turakhia, M. P., Turan, T. N., Wood, K. A. 2012; 43 (12): 3442-3453

    View details for Web of Science ID 000311497600063

    View details for PubMedID 22858728

  • Impact of Baseline Stroke Risk and Bleeding Risk on INR Control among Patients with Atrial Fibrillation on Warfarin: the TREAT-AF Study Turakhia, M. P., Than, C. T., Xu, X., Schmitt, S. K., Yang, F., Frayne, S. M., Phibbs, C. S., Holmes, T. H., Heidenreich, P. A. LIPPINCOTT WILLIAMS & WILKINS. 2012
  • Trends in the Incidence of Atrial Fibrillation in Older Patients Initiating Dialysis in the United States CIRCULATION Goldstein, B. A., Arce, C. M., Hlatky, M. A., Turakhia, M., Setoguchi, S., Winkelmayer, W. C. 2012; 126 (19): 2293-?

    Abstract

    One sixth of US dialysis patients 65 years of age have been diagnosed with atrial fibrillation/flutter (AF). Little is known, however, about the incidence of AF in this population.We identified 258 605 older patients (≥67 years of age) with fee-for-service Medicare initiating dialysis in 1995 to 2007, who had not been diagnosed with AF within the previous 2 years. Patients were followed for newly diagnosed AF. Multivariable proportional hazard regression was used to examine temporal trends and associations of race and ethnicity with incident AF. We also studied temporal trends in the mortality and risk of ischemic stroke after new AF. Over 514 395 person-years of follow-up, 76 252 patients experienced incident AF for a crude AF incidence rate of 148/1000 person-years. Incidence of AF increased by 11% (95% confidence interval, 5-16) from 1995 to 2007. Compared with non-Hispanic whites, blacks (-30%), Asians (-19%), Native Americans (-42%), and Hispanics (-29%) all had lower rates of incident AF. Mortality after incident AF decreased by 22% from 1995 to 2008. Even more pronounced reductions were seen for incident ischemic stroke during these years.The incidence of AF is high in older patients initiating dialysis in the United States and has been increasing over the 13 years of study. Mortality declined during that time but remained >50% during the first year after newly diagnosed AF. Because data on warfarin use were not available, we were unable to study whether trends toward better outcomes could be explained by higher rates of oral anticoagulation.

    View details for Web of Science ID 000310744100010

    View details for PubMedID 23032326

    View details for PubMedCentralID PMC3640842

  • Anticoagulation for atrial fibrillation in patients on dialysis: are the benefits worth the risks? CURRENT OPINION IN NEPHROLOGY AND HYPERTENSION Shen, J. I., Turakhia, M. P., Winkelmayer, W. C. 2012; 21 (6): 600-606

    Abstract

    Atrial fibrillation is common among patients with end-stage renal disease undergoing hemodialysis. Although oral anticoagulation is recommended for stroke prevention in most patients with atrial fibrillation, limited evidence is available to guide treatment in hemodialysis patients with this arrhythmia. We summarize the available evidence on the epidemiology of atrial fibrillation in dialysis patients and review the data on the effectiveness of oral anticoagulation in this population.Atrial fibrillation is increasingly common in patients undergoing chronic hemodialysis, especially among older patients wherein one in six patients is diagnosed with this arrhythmia. Patients with atrial fibrillation experience double the mortality of otherwise similar patients without it. Few hemodialysis patients with atrial fibrillation receive oral anticoagulation, which is consistently associated with excess risks of hemorrhagic stroke. Observational studies did not detect a beneficial association of oral anticoagulation with the risk of ischemic stroke, with some studies describing higher risks of ischemic stroke among warfarin users. New therapeutic options including one oral direct thrombin inhibitor and two oral factor Xa inhibitors have become available, but were not tested in patients with advanced kidney disease.Atrial fibrillation is increasingly common in patients undergoing hemodialysis, yet little is known about the optimal management of these patients. The current evidence does not support net benefits from oral anticoagulation in the dialysis population.

    View details for DOI 10.1097/MNH.0b013e32835856fd

    View details for Web of Science ID 000310061500006

    View details for PubMedID 23079746

  • Reply: Ability of microvolt T-wave alternans to modify risk assessment of ventricular tachyarrhythmic events: A meta-analysis AMERICAN HEART JOURNAL Turakhia, M. P., Gupta, A. 2012; 164 (4)
  • Latency of ECG Displays of Hospital Telemetry Systems A Science Advisory From the American Heart Association CIRCULATION Turakhia, M. P., Estes, N. A., Drew, B. J., Granger, C. B., Wang, P. J., Knight, B. P., Page, R. L. 2012; 126 (13): 1665-1669

    View details for DOI 10.1161/CIR.0b013e31826ae459

    View details for Web of Science ID 000309260600023

    View details for PubMedID 22927339

  • Abrupt bradycardia and grouped beating during treadmill testing: A mimic of upper rate behavior HEART RHYTHM Woods, C. E., Friday, K., Wang, P., Turakhia, M. P. 2012; 9 (7): 1165-1167

    View details for DOI 10.1016/j.hrthm.2011.12.020

    View details for Web of Science ID 000305616900031

    View details for PubMedID 22209946

  • Incidence and clinical predictors of low defibrillation safety margin at time of implantable defibrillator implantation JOURNAL OF INTERVENTIONAL CARDIAC ELECTROPHYSIOLOGY Cheng, Z., Turakhia, M., Lo, R., Gupta, A., Zei, P. C., Hsia, H. H., Al-Ahmad, A., Wang, P. J. 2012; 34 (1): 93-100

    Abstract

    Determination of the defibrillation safety margin (DSM) is the most common method of testing device effectiveness at the time of implantation of implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy defibrillator (CRTD). Low DSM remains a problem in clinical practice.The purpose of this study is to ascertain the incidence and clinical predictors of low DSM and the treatment strategies for low DSM in ICD or CRTD recipients.Selected ICD or CRTD recipients from January 2006 to May 2008 who underwent DSM test at the time of implantation were included. Low DSM patients were defined as patients who had a DSM within 10 J of the maximum delivered energy of the device. These patients were compared to patients who had DSM > 10 J.This study included 243 patients. Of these, 13 (5.3%) patients had low DSM, and 230 patients had adequate DSM. Patients with low DSM had a high prevalence of amiodarone use (69% vs 13%, p < 0.01), secondary prevention indications (69% vs 30%, p < 0.01), and a trend toward younger age (51 ± 18 vs 58 ± 15 years, p = 0.08). After adjustment for age and sex, amiodarone use was significantly associated with low DSM. All low DSM patients except one obtained adequate DSM after taking additional steps, including discontinuing amiodarone and starting sotalol, RV lead repositioning, adding a subcutaneous array or shock coil, changing single-coil to dual-coil lead, and upgrading to a high output device.The incidence of low DSM patients is low with high-energy devices. Amiodarone use is associated with low DSM, and its discontinuation or substitution with sotalol is one of a variety of available options for low DSM patients.

    View details for DOI 10.1007/s10840-011-9648-z

    View details for Web of Science ID 000303541200013

    View details for PubMedID 22391960

  • TRENDS IN THE INCIDENCE OF ATRIAL FIBRILLATION IN OLDER PATIENTS INITIATING DIALYSIS IN THE UNITED STATES 49th Congress of the European-Renal-Association/European-Dialysis-and-Transplant-Association (ERA-EDTA) Goldstein, B., Turakhia, M., Arce, C., Winkelmayer, W. OXFORD UNIV PRESS. 2012: 231–232
  • The prognostic value of early repolarization with ST-segment elevation in African Americans HEART RHYTHM Perez, M. V., Uberoi, A., Jain, N. A., Ashley, E., Turakhia, M. P., Froelicher, V. 2012; 9 (4): 558-565

    Abstract

    Increased prevalence of classic early repolarization, defined as ST-segment elevation (STE) in the absence of acute myocardial injury, in African Americans is well established. The prognostic value of this pattern in different ethnicities remains controversial.Measure association between early repolarization and cardiovascular mortality in African Americans.The resting electrocardiograms of 45,829 patients were evaluated at the Palo Alto Veterans Affairs Hospital. Subjects with inpatient status or electrocardiographic evidence of acute myocardial infarction were excluded, leaving 29,281 subjects. ST-segment elevation, defined as an elevation of >0.1 mV at the end of the QRS, was electronically flagged and visually adjudicated by 3 observers blinded to outcomes. An association between ethnicity and early repolarization was measured by using multivariate logistic regression. We analyzed associations between early repolarization and cardiovascular mortality by using the Cox proportional hazards regression analysis.Subjects were 13% women and 13.3% African Americans, with an average age of 55 years and followed for an average of 7.6 years, resulting in 1995 cardiovascular deaths. There were 479 subjects with lateral STE and 185 with inferior STE. After adjustment for age, sex, heart rate, and coronary artery disease, African American ethnicity was associated with lateral or inferior STE (odds ratio 3.1; P = .0001). While lateral or inferior STE in non-African Americans was independently associated with cardiovascular death (hazard ratio 1.6; P = .02), it was not associated with cardiovascular death in African Americans (hazard ratio 0.75; P = .50).Although early repolarization is more prevalent in African Americans, it is not predictive of cardiovascular death in this population and may represent a distinct electrophysiologic phenomenon.

    View details for DOI 10.1016/j.hrthm.2011.11.020

    View details for Web of Science ID 000302258100020

    View details for PubMedID 22094072

  • AMIODARONE USE IS NOT ASSOCIATED WITH MORTALITY IN PATIENTS WITH ATRIAL FIBRILLATION AND KIDNEY DYSFUNCTION OR DIALYSIS: THE TREAT-AF STUDY 61st Annual Scientific Session and Expo of the American-College-of-Cardiology (ACC)/Conference on ACC-i2 with TCT Turakhia, M., Yang, F., Xu, X., Winkelmayer, W., Hoang, D., Heidenreich, P. ELSEVIER SCIENCE INC. 2012: E682–E682
  • CARDIOVASCULAR HOSPITALIZATION IS A STRONG PREDICTOR OF MORTALITY IN MEDICARE BENEFICIARIES WITH NEWLY DIAGNOSED ATRIAL FIBRILLATION 61st Annual Scientific Session and Expo of the American-College-of-Cardiology (ACC)/Conference on ACC-i2 with TCT Turakhia, M., Solomon, M., Jhaveri, M., Davis, P., Conrad, R., Summers, N., Lakdawalla, D. ELSEVIER SCIENCE INC. 2012: E723–E723
  • INTERACTION AMONG DIGOXIN USE, KIDNEY FUNCTION, AND MORTALITY IN PATIENTS WITH ATRIAL FIBRILLATION: THE TREAT-AF STUDY 61st Annual Scientific Session and Expo of the American-College-of-Cardiology (ACC)/Conference on ACC-i2 with TCT Turakhia, M., Yang, F., Xu, X., Winkelmayer, W., Hoang, D., Heidenreich, P. ELSEVIER SCIENCE INC. 2012: E685–E685
  • Ability of microvolt T-wave alternans to modify risk assessment of ventricular tachyarrhythmic events: A meta-analysis AMERICAN HEART JOURNAL Gupta, A., Hoang, D. D., Karliner, L., Tice, J. A., Heidenreich, P., Wang, P. J., Turakhia, M. P. 2012; 163 (3): 354-364

    Abstract

    Prior studies have indicated that the magnitude of risk association of microvolt T-wave alternans (MTWA) testing appears to vary with the population studied. We performed a meta-analysis to determine the ability of MTWA to modify risk assessment of ventricular tachyarrhythmic events (VTEs) and sudden cardiac death (SCD) across a series of patient risk profiles using likelihood ratio (LR) testing, a measure of test performance independent of disease prevalence.We identified original research articles published from January 1990 to January 2011 that investigate spectrally derived MTWA. Ventricular tachyarrhythmic event was defined as the total and arrhythmic mortality and nonfatal sustained or implantable cardioverter-defibrillator-treated ventricular tachyarrhythmias. Summary estimates were created for positive and nonnegative MTWA results using a random-effects model and were expressed as positive (LR+) and negative (LR-) LRs.Of 1,534 articles, 20 prospective cohort studies met our inclusion criteria, consisting of 5,945 subjects predominantly with prior myocardial infarction or left ventricular dysfunction. Although there was a modest association between positive MTWA and VTE (relative risk 2.45, 1.58-3.79) and nonnegative MTWA and VTE (3.68, 2.23-6.07), test performance was poor (positive MTWA: LR+ 1.78, LR- 0.43; nonnegative MTWA: LR+ 1.38, LR- 0.56). Subgroup analyses of subjects classified as prior VTE, post-myocardial infarction, SCD-HeFT type, and MADIT-II type had a similar poor test performance. A negative MTWA result would decrease the annualized risk of VTE from 8.85% to 6.37% in MADIT-II-type patients and from 5.91% to 2.60% in SCD-HeFT-type patients.Despite a modest association, results of spectrally derived MTWA testing do not sufficiently modify the risk of VTE to change clinical decisions.

    View details for DOI 10.1016/j.ahj.2011.11.021

    View details for Web of Science ID 000301597200010

    View details for PubMedID 22424005

  • Left Atrial Function Predicts Heart Failure Hospitalization in Subjects With Preserved Ejection Fraction and Coronary Heart Disease Longitudinal Data From the Heart and Soul Study JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Welles, C. C., Ku, I. A., Kwan, D. M., Whooley, M. A., Schiller, N. B., Turakhia, M. P. 2012; 59 (7): 673-680

    Abstract

    This study sought to determine whether left atrial (LA) dysfunction predicts heart failure (HF) hospitalization in subjects with preserved baseline ejection fraction (EF).Among patients with preserved EF, factors leading to HF are not fully understood. Cross-sectional studies have demonstrated LA dysfunction at the time of HF, but longitudinal data on antecedent atrial function are lacking.We performed resting transthoracic echocardiography in 855 subjects with coronary heart disease and EF ≥50%. Left atrial functional index (LAFI) was calculated as ([LA emptying fraction × left ventricular outflow tract-velocity time integral] / [indexed LA end-systolic volume]), where LA emptying fraction was defined as (LA end-systolic volume--LA end-diastolic volume) / LA end-systolic volume. We used Cox models to evaluate the association between LAFI and HF hospitalization.Over a median follow-up of 7.9 years, 106 participants (12.4%) were hospitalized for HF. Rates of HF hospitalization were inversely proportional to quartile (Q) of LAFI: Q1, 47 per 1,000 person-years; Q2, 18.3; Q3, 9.6; and Q4, 5.3 (p < 0.001). Each standard deviation decrease in LAFI was associated with a 2.6-fold increased hazard of adverse cardiovascular outcomes (unadjusted hazard ratio: 2.6, 95% confidence interval: 2.1 to 3.3, p < 0.001), and the association persisted even after adjustment for clinical risk factors, N-terminal pro-B-type natriuretic peptide, and a wide range of echocardiographic parameters (adjusted hazard ratio: 1.5, 95% confidence interval: 1.0 to 2.1, p = 0.05).Left atrial dysfunction independently predicts HF hospitalization in subjects with coronary heart disease and preserved baseline EF. The LAFI may be useful for HF risk stratification, and LA dysfunction may be a potential therapeutic target.

    View details for DOI 10.1016/j.jacc.2011.11.012

    View details for Web of Science ID 000300393900008

    View details for PubMedID 22322084

    View details for PubMedCentralID PMC3282121

  • Cost-effectiveness of pharmacologic and invasive therapies for stroke prophylaxis in atrial fibrillation JOURNAL OF CARDIOVASCULAR MEDICINE Solomon, M. D., Ullal, A. J., Hoang, D. D., Freeman, J. V., Heidenreich, P., Turakhia, M. P. 2012; 13 (2): 86-96

    Abstract

    Atrial fibrillation is an abnormal heart rhythm characterized by rapid, disorganized activation (fibrillation) of the left and right atria of the heart, and is responsible for 15% of 700,000 strokes in the United States each year. There are multiple pharmacologic and nonpharmacologic therapies used for stroke prevention in atrial fibrillation, including vitamin K antagonists such as warfarin, antiplatelet agents such as aspirin and clopidogrel, and newer agents such as dabigatran, rivaroxaban and apixaban. Nonpharmacologic therapies involve excluding the left atrial appendage from the systemic circulation by surgical ligation or excision, percutaneous ligation, or endovascular implantation of a left atrial occlusion device. Because atrial fibrillation-related stroke is preventable, a comparison of the value of these interventions by cost-effectiveness analysis (CEA) could inform clinical and health policy recommendations. In this article, we review the principles of CEA and identify 11 articles that examine CEA of stroke prophylaxis strategies in atrial fibrillation. Although most studies evaluate aspirin and warfarin across a variety of atrial fibrillation stroke risk profiles, we also review new literature on new pharmacologic therapies such as direct thrombin inhibitors and discuss the potential value of device-based therapies.

    View details for DOI 10.2459/JCM.0b013e32834f23cf

    View details for Web of Science ID 000299652200002

    View details for PubMedID 22193838

  • Clinical Reminders to Providers of Patients with Depressed Left Ventricular Ejection Fraction Increase Defibrillator Implantation: A Randomized Trial Scientific Sessions of the American-Heart-Association/Resuscitation Science Symposium Gupta, A., Gholami, P., Turakhia, M., Friday, K., Heidenreich, P. LIPPINCOTT WILLIAMS & WILKINS. 2011
  • Early Repolarization in an Ambulatory Clinical Population CIRCULATION Uberoi, A., Jain, N. A., Perez, M., Weinkopff, A., Ashley, E., Hadley, D., Turakhia, M. P., Froelicher, V. 2011; 124 (20): 2208-2214

    Abstract

    The significance of early repolarization, particularly regarding the morphology of the R-wave downslope, has come under question.We evaluated 29 281 resting ambulatory ECGs from the VA Palo Alto Health Care System. With PR interval as the isoelectric line and amplitude criteria ≥0.1 mV, ST-segment elevation is defined at the end of the QRS, J wave as an upward deflection, and slur as a conduction delay on the QRS downstroke. Associations of ST-segment elevation patterns, J waves, and slurs with cardiovascular mortality were analyzed with Cox analysis. With a median follow-up of 7.6 years, there were 1995 cardiac deaths. Of 29 281 subjects, 87% were male (55±14 years) and 13% were female (56±17 years); 13% were black, 6% were Hispanic, and 81% were white or other. Six hundred sixty-four (2.3%) had inferior or lateral ST-segment elevation: 185 (0.6%) in inferior leads and 479 (1.6%) in lateral leads, 163 (0.6%) in both, and 0.4% had global elevation. A total of 4041 ECGs were analyzed with enhanced display, and 583 (14%) had J waves or slurring, which were more prevalent in those with than in those without ST-segment elevation (61% versus 13%; P<0.001). ST-segment elevation occurred more in those with than in those without J waves or slurs (12% versus 1.3%; P<0.001). Except when involving only inferior leads, all components of early repolarization were more common in young individuals, male subjects, blacks, and those with bradycardia. All patterns and components of early repolarization were associated with decreased cardiovascular mortality, but this was not significant after adjustment for age.We found no significant association between any components of early repolarization and cardiac mortality.

    View details for DOI 10.1161/CIRCULATIONAHA.111.047191

    View details for Web of Science ID 000297060700013

    View details for PubMedID 21986288

  • JICE goes "social" JOURNAL OF INTERVENTIONAL CARDIAC ELECTROPHYSIOLOGY Turakhia, M. P. 2011; 32 (2): 79-80

    Abstract

    Social media is transforming health care. The Journal of Interventional Cardiac Electrophysiology (JICE) has launched its own social media presence and is now on Facebook. JICE will post each issue's table of contents, special articles, online-first publications to allow real-time notifications to JICE's readers and fans of our Facebook page. We encourage you to take the plunge and connect to our Facebook page.

    View details for DOI 10.1007/s10840-011-9621-x

    View details for Web of Science ID 000297556800001

    View details for PubMedID 21972151

  • The CHADS(2) score predicts ischemic stroke in the absence of atrial fibrillation among subjects with coronary heart disease: Data from the Heart and Soul Study AMERICAN HEART JOURNAL Welles, C. C., Whooley, M. A., Na, B., Ganz, P., Schiller, N. B., Turakhia, M. P. 2011; 162 (3): 555-561

    Abstract

    We sought to evaluate the prognostic performance of the CHADS(2) score for prediction of ischemic stroke/transient ischemic attack (TIA) in subjects with coronary heart disease (CHD) without atrial fibrillation (AF).In 916 nonanticoagulated outpatients with stable CHD and no AF by baseline electrocardiogram, we calculated CHADS(2) scores (congestive heart failure, hypertension, age ≥75 years, diabetes [1 point each], and prior stroke or TIA [2 points]). The primary outcome was time to ischemic stroke or TIA over a mean follow-up of 6.4 ± 2.3 years.Over 5,821 person-years of follow-up, 40 subjects had an ischemic stroke/TIA (rate 0.69/100 person-years, 95% CI 0.50-0.94). Compared with subjects with low (0-1) CHADS(2) scores, those with intermediate (2-3) and high (4-6) CHADS(2) scores had an increased rate of stroke/TIA, even after adjustment for age, tobacco, antiplatelet therapy, statins, and angiotensin inhibitors (CHADS(2) score 2-3: HR 2.4, 95% CI 1.1-5.3, P = .03; CHADS(2) score 4-6: HR 4.0, 95% CI 1.5-10.6, P = .006). Model discrimination (c-statistic = 0.65) was comparable with CHADS(2) model fit in published AF-only cohorts.The CHADS(2) score predicts ischemic stroke/TIA in subjects with stable CHD and no baseline AF. The event rate in non-AF subjects with high CHADS(2) scores (5-6) was comparable with published rates in AF patients with moderate CHADS(2) scores (1-2), a population known to derive benefit from stroke prevention therapies. These findings should inform efforts to determine whether stroke prevention therapies or screening for silent AF may benefit subjects with stable CHD and high CHADS(2) scores.

    View details for DOI 10.1016/j.ahj.2011.05.023

    View details for Web of Science ID 000294447400022

    View details for PubMedID 21884876

    View details for PubMedCentralID PMC3199107

  • Dabigatran Compared With Warfarin for Stroke Prevention in Atrial Fibrillation ANNALS OF INTERNAL MEDICINE Freeman, J. V., Turakhia, M. P. 2011; 154 (8): 570-571
  • THE CHADS2 SCORE PREDICTS ISCHEMIC STROKE IN THE ABSENCE OF ATRIAL FIBRILLATION AMONG PATIENTS WITH CORONARY HEART DISEASE: DATA FROM THE HEART AND SOUL STUDY Welles, C. C., Na, B., Whooley, M. A., Turakhia, M. P. ELSEVIER SCIENCE INC. 2011: E607
  • Cost-Effectiveness of Dabigatran Compared With Warfarin for Stroke Prevention in Atrial Fibrillation ANNALS OF INTERNAL MEDICINE Freeman, J. V., Zhu, R. P., Owens, D. K., Garber, A. M., Hutton, D. W., Go, A. S., Wang, P. J., Turakhia, M. P. 2011; 154 (1): 1-U129

    Abstract

    Warfarin reduces the risk for ischemic stroke in patients with atrial fibrillation (AF) but increases the risk for hemorrhage. Dabigatran is a fixed-dose, oral direct thrombin inhibitor with similar or reduced rates of ischemic stroke and intracranial hemorrhage in patients with AF compared with those of warfarin.To estimate the quality-adjusted survival, costs, and cost-effectiveness of dabigatran compared with adjusted-dose warfarin for preventing ischemic stroke in patients 65 years or older with nonvalvular AF.Markov decision model.The RE-LY (Randomized Evaluation of Long-Term Anticoagulation Therapy) trial and other published studies of anticoagulation. The cost of dabigatran was estimated on the basis of pricing in the United Kingdom.Patients aged 65 years or older with nonvalvular AF and risk factors for stroke (CHADS₂ score ≥1 or equivalent) and no contraindications to anticoagulation.Lifetime.Societal.Warfarin anticoagulation (target international normalized ratio, 2.0 to 3.0); dabigatran, 110 mg twice daily (low dose); and dabigatran, 150 mg twice daily (high dose).Quality-adjusted life-years (QALYs), costs (in 2008 U.S. dollars), and incremental cost-effectiveness ratios.The quality-adjusted life expectancy was 10.28 QALYs with warfarin, 10.70 QALYs with low-dose dabigatran, and 10.84 QALYs with high-dose dabigatran. Total costs were $143 193 for warfarin, $164 576 for low-dose dabigatran, and $168 398 for high-dose dabigatran. The incremental cost-effectiveness ratios compared with warfarin were $51 229 per QALY for low-dose dabigatran and $45 372 per QALY for high-dose dabigatran.The model was sensitive to the cost of dabigatran but was relatively insensitive to other model inputs. The incremental cost-effectiveness ratio increased to $50 000 per QALY at a cost of $13.70 per day for high-dose dabigatran but remained less than $85 000 per QALY over the full range of model inputs evaluated. The cost-effectiveness of high-dose dabigatran improved with increasing risk for stroke and intracranial hemorrhage.Event rates were largely derived from a single randomized clinical trial and extrapolated to a 35-year time frame from clinical trials with approximately 2-year follow-up.In patients aged 65 years or older with nonvalvular AF at increased risk for stroke (CHADS₂ score ≥1 or equivalent), dabigatran may be a cost-effective alternative to warfarin depending on pricing in the United States.American Heart Association and Veterans Affairs Health Services Research & Development Service.

    View details for Web of Science ID 000285830900001

    View details for PubMedID 21041570

  • Quality of Stroke Prevention Care in Atrial Fibrillation Many Moving Targets CIRCULATION-CARDIOVASCULAR QUALITY AND OUTCOMES Turakhia, M. P. 2011; 4 (1): 5-8
  • Using Restriction to Minimize Bias in Observational Studies JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION Turakhia, M. P., Heidenreich, P. A. 2010; 304 (21): 2359-2359

    View details for Web of Science ID 000284763900014

    View details for PubMedID 21119082

  • Inappropriate Pacing in a Patient with Managed Ventricular Pacing: What Is the Cause? HEART RHYTHM Perez, M. V., Al-Ahmad, A. A., Wang, P. J., Turakhia, M. P. 2010; 7 (12)
  • Sudden Cardiac Death and Implantable Cardioverter-Defibrillators AMERICAN FAMILY PHYSICIAN Turakhia, M. P. 2010; 82 (11): 1357-1366

    Abstract

    Sudden cardiac death is a major public health problem, affecting 500,000 patients in the United States annually. An implantable cardioverter-defibrillator (ICD) can terminate malignant ventricular arrhythmias and has been shown to improve survival in high-risk populations. Although sudden cardiac death is a heterogeneous condition, left ventricular ejection fraction of 35 percent or less remains the single best factor to stratify patients for prophylactic ICD implantation, and randomized trials have shown mortality benefit in this population. Therefore, in patients with heart disease, assessment of ejection fraction remains the most important step to identify patients at risk of sudden cardiac death who would benefit from ICD implantation. Physician understanding of each patient's ICD type, indication, etiology of heart disease, and cardiovascular status is essential for optimal care. If the ICD was placed for secondary prevention, the circumstances relating to the index event should be explored. Evaluation of defibrillator shocks merits careful assessment of the patient's cardiovascular status. Consultation with a subspecialist and interrogation of the ICD can determine if shocks were appropriate or inappropriate and can facilitate management.

    View details for Web of Science ID 000208405500010

  • Developing the Safety of Atrial Fibrillation Ablation Registry Initiative (SAFARI) as a collaborative pan-stakeholder critical path registry model: A Cardiac Safety Research Consortium "Incubator" Think Tank AMERICAN HEART JOURNAL Al-Khatib, S. M., Calkins, H., Eloff, B. C., Kowey, P., Hammill, S. C., Ellenbogen, K. A., Marinac-Dabic, D., Waldo, A. L., Brindis, R. G., Wilbur, D. J., Jackman, W. M., Yaross, M. S., Russo, A. M., Prystowsky, E., Varosy, P. D., Gross, T., Pinnow, E., Turakhia, M. P., Krucoff, M. W. 2010; 160 (4): 619-U249

    Abstract

    Although several randomized clinical trials have demonstrated the safety and efficacy of catheter ablation of atrial fibrillation (AF) in experienced centers, the outcomes of this procedure in routine clinical practice and in patients with persistent and long-standing persistent AF remain uncertain. Brisk adoption of this therapy by physicians with diverse training and experience highlights potential concerns regarding the safety and effectiveness of this procedure. Some of these concerns could be addressed by a national registry of AF ablation procedures such as the Safety of Atrial Fibrillation Ablation Registry Initiative that was initially proposed at a Cardiac Safety Research Consortium Think Tank meeting in April 2009. In January 2010, the Cardiac Safety Research Consortium, in collaboration with the Duke Clinical Research Institute, the US Food and Drug Administration, the American College of Cardiology, and the Heart Rhythm Society, held a follow-up meeting of experts in the field to review the construct and progress to date. Other participants included the National Heart, Lung, and Blood Institute; the Centers for Medicare and Medicaid Services; the Agency for Healthcare Research and Quality; the AdvaMed AF working group; and additional industry representatives. This article summarizes the discussions that occurred at the meeting of the state of the Safety of Atrial Fibrillation Ablation Registry Initiative, the identification of a clear pathway for its implementation, and the exploration of solutions to potential issues in the execution of this registry.

    View details for DOI 10.1016/j.ahj.2010.06.044

    View details for Web of Science ID 000282677300010

    View details for PubMedID 20934554

  • Prevalence of Metabolic Syndrome in South Asians Residing in the United States METABOLIC SYNDROME AND RELATED DISORDERS Flowers, E., Molina, C., Mathur, A., Prasad, M., Abrams, L., Sathe, A., Malhotra, D., Basra, R., Malgesini, N., Ratnam, G., Aouizerat, B. E., Turakhia, M. P. 2010; 8 (5): 417-423

    Abstract

    The aim of this study was to define the prevalence of the metabolic syndrome and its component risk factors among individuals of South Asian origin living in the United States.We analyzed baseline data from 1,445 participants enrolled in a cohort study investigating risk factors for cardiovascular disease in South Asians. We defined the metabolic syndrome using the International Diabetes Federation criteria for waist circumference (>90 cm for men; >80 cm, women), triglycerides (>150 mg/dL), high-density lipoprotein cholesterol (HDL-C) (<40 mg/dL (men), < mg/dL (women)), blood pressure (>135/80 mmHg), and fasting glucose (>100 mg/dL).The mean age was 43 +/-10 years, and 30% of participants were women. The prevalence of metabolic syndrome was 27% (31% men vs. 17% women, P < 0.05). Fifty-nine percent of the cohort had high waist circumference (58% men vs. 62% women, P = not significant [N.S.]), 47% had low HDL-C [46% men vs. 48% women (NS)], 19% had elevated triglycerides (23% men vs. 8% women, P < 0.05), 14% had hypertension (16% men vs. 9% women, P < 0.05), and 13% had elevated fasting glucose (18% men vs. 11% women, P < 0.05). The most common metabolic syndrome phenotype is low HDL-C with elevated triglycerides.Although the prevalence of the metabolic syndrome is lower than previous reports of South Asians, the prevalence is still unacceptably high despite the presence of protective demographic factors.

    View details for DOI 10.1089/met.2009.0097

    View details for Web of Science ID 000282809400006

    View details for PubMedID 20939706

  • Inappropriate pacing in a patient with managed ventricular pacing: What is the cause? HEART RHYTHM Perez, M. V., Al-Ahmad, A. A., Wang, P. J., Turakhia, M. P. 2010; 7 (9): 1336-1337

    Abstract

    A case of inappropriate atrial pacing in a patient with a pacemaker programmed with Managed Ventricular Pacing (MVP) mode, a proprietary algorithm in Medtronic devices, is presented. The patient was an 84-year-old woman who presented in sinus rhythm with complete atrioventricular block. A dual-chamber pacemaker was implanted and programmed to an MVP pacing mode. After the implant, the patient developed a relatively slow atrial tachyarrhythmia with 2:1 atrioventricular block and inappropriate atrial pacing, followed by a delay in tracking of the atrial tachyarrhythmia. The mechanisms for these behaviors are described.

    View details for DOI 10.1016/j.hrthm.2010.04.028

    View details for Web of Science ID 000281444100033

    View details for PubMedID 20435165

  • Predicting Heart Failure Hospitalization and Mortality by Quantitative Echocardiography: Is Body Surface Area the Indexing Method of Choice? The Heart and Soul Study JOURNAL OF THE AMERICAN SOCIETY OF ECHOCARDIOGRAPHY Ristow, B., Ali, S., Na, B., Turakhia, M. P., Whooley, M. A., Schiller, N. B. 2010; 23 (4): 406-413

    Abstract

    Echocardiographic measurements of left ventricular (LV) mass, left atrial (LA) volume, and LV end-systolic volume (ESV) predict heart failure (HF) hospitalization and mortality. Indexing measurements by body size is thought to establish limits of normality among individuals varying in body habitus. The American Society of Echocardiography recommends dividing measurements by body surface area (BSA), but others have advocated alternative indexing methods.Echocardiographic measurements were collected in 1024 ambulatory adults with coronary artery disease. LV mass, LA volume, and LV ESV were calculated using truncated ellipse method and biplane method of disk formulae. Comparison between raw measurements and measurements divided by indexing parameters was made by hazard ratios per standard deviation increase in variable and c-statistics for BSA, BSA(0.43), BSA(1.5), height, height(0.25), height(2), height(2.7), body weight (BW), BW(0.26), body mass index (BMI), and BMI(0.27).Mean LV mass was 192 +/- 57 g, mean LA volume was 65 +/- 24 mL, and mean LV ESV was 41 +/- 26 mL. Average height was 171 +/- 9 cm, average BSA was 1.94 +/- 0.22 m(2), and average BMI was 28.4 +/- 5.3 kg/m(2). At an average follow-up of 5.6 +/- 1.8 years, there were 148 HF hospitalizations, 71 cardiovascular (CV) deaths, and 269 all-cause deaths. There was excellent correlation between raw measurements and those indexed by height (r = 0.98-0.99), and moderate correlation between raw measurements and those indexed by BW (r = 0.73-0.94). C-statistics and hazard ratios per standard deviation increase in indexed variables were similar for HF hospitalization, CV mortality, and all-cause mortality. There were no significant differences among indexing methods in ability to predict outcomes.The choice of indexing method by parameters of BSA, height, BW, and BMI does not affect the clinical usefulness of LV mass, LA volume, and LV ESV in predicting HF hospitalization, CV mortality, or all-cause mortality among ambulatory adults with coronary artery disease. Continued use of BSA to index measurements of LV mass, LA volume, and LV ESV is acceptable.

    View details for DOI 10.1016/j.echo.2010.01.019

    View details for Web of Science ID 000276248600012

    View details for PubMedID 20202792

    View details for PubMedCentralID PMC2886012

  • Atrial Mechanical Function Using Left Atrial Pressure Waveform Analysis in Persistent and Paroxysmal Atrial Fibrillation Patients 82nd National Conference and Exhibitions and Scientific Sessions of the American-Heart-Association Cheng, Z., Lo, R., Gupta, A., Perez, M., Zei, P., Hsia, H. H., Turakhia, M., Al-Ahmad, A., Wang, P. J. LIPPINCOTT WILLIAMS & WILKINS. 2009: S628–S628
  • Increase in end-systolic volume after exercise independently predicts mortality in patients with coronary heart disease: data from the Heart and Soul Study EUROPEAN HEART JOURNAL Turakhia, M. P., McManus, D. D., Whooley, M. A., Schiller, N. B. 2009; 30 (20): 2478-2484

    Abstract

    The predictive value of changes in global left ventricular (LV) size after exercise has not been studied. Left ventricular end-systolic volume (ESV) is a relatively load-independent echocardiographic marker of contractility that is easily measured. We investigated the role of the change in ESV at rest and after peak exercise on mortality among patients with stable coronary heart disease (CHD).We performed exercise treadmill testing with stress echocardiography in 934 ambulatory subjects with CHD. End-systolic volume was measured immediately before and after exercise using 2D echocardiography. We defined ESV reversal as an increase in ESV after exercise, and we examined the association of ESV reversal with all-cause mortality during a median follow-up of 3.92 years. Of the 934 participants, 199 (21%) had ESV reversal. At the end of follow-up, mortality was higher among participants with ESV reversal than those without (26 vs. 11%; P < 0.001). After adjustment for clinical covariates, ESV reversal remained predictive of all-cause mortality (HR 2.0; 95% CI 1.4-2.9; P = 0.001). The association of ESV reversal with mortality also persisted after adjustment for exercise-induced wall-motion abnormalities (HR 1.7; 95% CI 1.1-2.3, P = 0.006). To determine if the effect of ESV reversal was independent from other echocardiographic measurements, we created a separate model adjusting for resting LV ejection fraction, ESV, end-diastolic volume, and LV mass. End-systolic volume reversal was the only significant predictor of mortality in this model (HR 2.1, 95% CI 1.4-3.0, P < 0.001).End-systolic volume reversal is a novel parameter that independently predicts mortality in patients with CHD undergoing exercise treadmill echocardiography, even after adjustment for a wide range of clinical, echocardiographic, and treadmill exercise variables. Because measurement of ESV is simple, reproducible, and requires no additional imaging views, identification of ESV reversal during exercise echocardiography can provide useful complementary information for risk stratification.

    View details for DOI 10.1093/eurheartj/ehp270

    View details for Web of Science ID 000270985300020

    View details for PubMedID 19578167

    View details for PubMedCentralID PMC2761597

  • "Low ejection fraction prophylaxis" with implantable defibrillators in the elderly: Call for a randomized trial? HEART RHYTHM Turakhia, M. P., Wang, P. J. 2009; 6 (8): 1144-1145

    View details for DOI 10.1016/j.hrthm.2009.04.031

    View details for Web of Science ID 000268867700006

    View details for PubMedID 19632625

  • Polymorphic Ventricular Tachycardia? JOURNAL OF HOSPITAL MEDICINE Davis, E., Hoffmayer, K., Turakhia, M., Goldschlager, N. 2009; 4 (2): 140-141

    View details for DOI 10.1002/jhm.419

    View details for Web of Science ID 000263807400010

    View details for PubMedID 19219929

  • Rates and severity of perforation from implantable cardioverter-defibrillator leads: A 4-year study JOURNAL OF INTERVENTIONAL CARDIAC ELECTROPHYSIOLOGY Turakhia, M., Prasad, M., Olgin, J., Badhwar, N., Tseng, Z. H., Lee, R., Marcus, G. M., Lee, B. K. 2009; 24 (1): 47-52

    Abstract

    Although recent case reports and one small single-year observational study report a substantially increased rate of perforation with the St. Jude Riata series defibrillator lead, these results have not been externally validated.From 2004 to 2007, 593 implantable cardioverter-defibrillator (ICD) implants were performed by six faculty and 13 fellows at four University of California, San Francisco, CA, USA and affiliate hospitals. An electronic medical records system was systematically searched to identify clinically significant cases of ICD lead dislodgment or perforation. Of 307 (56%) St. Jude leads (all Riata series 6.3- and 7.3-French leads), 188 (29%) Medtronic leads (including 99 Sprint Fidelis 6.6 French leads), and 98 (15%) Guidant/Boston Scientific leads, there were three perforations in 593 cases (0.51%). One perforation occurred with a Medtronic Sprint Fidelis 6949 lead (0.53%), and two with a St. Jude Riata 1581 lead (0.65%). There were no statistically significant differences in perforation or dislodgement rates between manufacturers or lead models (p = NS for all). In both cases of perforation with the St. Jude Riata leads, the lead tip perforated through the pericardium into the pleural space.In our 4-year series of ICD implants, perforation and dislodgement rates were low, similar across all lead makes and models, and well below published and accepted complication rates. Our findings contradict previously-reported higher rates of perforation with the Riata lead. Registry and product performance reports should also classify complications by severity and outcome to provide a more complete assessment of product safety.

    View details for DOI 10.1007/s10840-008-9308-0

    View details for Web of Science ID 000262987700008

    View details for PubMedID 18855128

  • Wolff-Parkinson-White syndrome: where is the pathway? Indian pacing and electrophysiology journal Turakhia, M. P., Scheinman, M., Badhwar, N. 2009; 9 (2): 130-133

    Abstract

    A 31-year old male presented with atrial fibrillation and ventricular preexcitation that was positive in leads V1-V4, negative in lead II, and positive in lead AVR. The patient was cardioverted and invasive electrophysiologic study was performed. Based on the ECG findings, the coronary sinus and its branches were interrogated during orthodromic atrioventricular reentrant tachycardia. The earliest local activation was seen in the true coronary sinus lumen at the bifurcation of the posterolateral branch. Radiofrequency energy application at this area led to loss of preexcitation. When localizing left septal and posterior accessory pathways, ventricular preexcitation that is both negative in II and positive in AVR has been shown in previous studies to be highly sensitive and specific for a subepicardial location. Therefore, investigation of the coronary sinus and its branches may allow for effective ablation without the need for left ventricular access.

    View details for PubMedID 19308285

    View details for PubMedCentralID PMC2655076

  • Impact of Remote Magnetic Catheter Navigation on Ablation Fluoroscopy and Procedure Time PACE-PACING AND CLINICAL ELECTROPHYSIOLOGY Kim, A. M., Turakhia, M., Lu, J., Badhwar, N., Lee, B. K., Lee, R. J., Marcus, G. M., Tseng, Z. H., Scheinman, M., Olgin, J. E. 2008; 31 (11): 1399-1404

    Abstract

    Remote magnetic catheter navigation (RCN) is gaining acceptance in clinical cardiac electrophysiology, but details regarding how RCN affects procedure execution are not well characterized.From January 1, 2005, to November 30, 2007, 721 cases were retrospectively analyzed and compared. Of these, 127 used RCN and 594 used manual catheter navigation (MCN). Data including procedure time, fluoroscopy time, ablation catheter, procedural success, and complications were extracted from our procedure database and compared between RCN and MCN.RCN use significantly decreased fluoroscopy time for atrial fibrillation (AF) ablation (-29 minutes, P < 0.001), atrioventricular nodal reentrant tachycardia ablation (-14 minutes, P < 0.001), and atrioventricular reentrant tachycardia ablation (-18 minutes, P = 0.045). While RCN significantly increased mean procedure time for AF (+36 minutes, P = 0.003) and atypical atrial flutter cases (+116 minutes, P = 0.016), RCN AF procedure time diminished with increasing number of cases performed. Two cases of tamponade occurred during AF ablation using MCN (2.2%, 2 of 91 cases). No tamponade occurred during all 75 AF ablations with RCN.RCN can reduce fluoroscopy time and may reduce complications during catheter ablation. While it may increase total procedure duration, procedure times decrease with increasing operator experience. (PACE 2008; 31:1399-1404).

    View details for DOI 10.1111/j.1540-8159.2008.01202.x

    View details for Web of Science ID 000262203600005

    View details for PubMedID 18950296

  • Prognostic Significance of Increased Left Ventricular Mass Index to Mortality and Sudden Death in Patients With Stable Coronary Heart Disease (from the Heart and Soul Study) AMERICAN JOURNAL OF CARDIOLOGY Turakhia, M. P., Schiller, N. B., Whooley, M. A. 2008; 102 (9): 1131-1135

    Abstract

    Data are limited about the significance of left ventricular (LV) hypertrophy or mass in patients with coronary heart disease (CHD), particularly in the setting of normal ejection fraction (EF). The association of LV mass index with all-cause mortality and sudden death in a cohort with CHD was evaluated. Using transthoracic echocardiography, LV mass normalized to body surface area was measured in 1,016 subjects with stable CHD. Cox proportional hazards models were used to examine the association of LV mass index and LV hypertrophy (LV mass index >95 g/m(2) in women and >115 in men) with time to death and time to sudden or arrhythmic death. Mean LV mass index was 101 +/- 27 g/m(2) in men and 88 +/- 23 in women. During a mean follow-up of 3.55 years, there were 146 deaths and 34 sudden or arrhythmic deaths. Total mortality was higher in subjects with LV hypertrophy (25% vs 11%, p <0.001), as was mortality from sudden or arrhythmic death (6.7% vs 2.2%, p = 0.001). After adjustment for age, gender, cardiovascular risk factors, and medical therapy, LV hypertrophy was associated with both all-cause mortality (hazard ratio 2.0, p <0.001) and sudden or arrhythmic death (hazard ratio 3.1, p = 0.003). Findings were similar in the subgroup with EF > or =55% (mortality hazard ratio 1.8, p = 0.02; sudden and arrhythmic death hazard ratio 3.1, p = 0.02). Analyzed as a continuous variable, every 20-unit increase in LV mass index increased the adjusted hazard of death by 22% (p = 0.001) and adjusted hazard of sudden or arrhythmic death by 40% (p = 0.004). In conclusion, in patients with stable CHD, increased LV mass index was independently associated with all-cause mortality and sudden or arrhythmic death, even in subjects with normal EF.

    View details for DOI 10.1016/j.amjcard.2008.06.030

    View details for Web of Science ID 000261007500003

    View details for PubMedID 18940278

    View details for PubMedCentralID PMC2583450

  • Impact of advanced age on survival in patients with implantable cardioverter defibrillators EUROPACE Pellegrini, C. N., Lee, K., Olgin, J. E., Turakhia, M. P., Tseng, Z. H., Lee, R., Badhwar, N., Lee, B., Varosy, P. D. 2008; 10 (11): 1296-1301

    Abstract

    Given the selectivity of clinical trial patients and meager representation of elderly in the major implantable cardioverter defibrillator (ICD) randomized trials (<25%), whether such data apply to elderly patients overall is unclear. The purpose of our study is to understand the influence of age on mortality after ICD implantation.We performed a retrospective cohort study of 502 consecutive patients receiving ICDs from 1993 to 2003 at a single university hospital. The primary predictor was patient age, categorized as <65, 65-75, and >75 years at ICD implantation. The primary outcome was time to death. Mean follow-up was 4 years. Median survival after ICD implantation was 5.3 years among subjects >75 years, less than half that of the youngest group. After adjusting for potential confounders, compared with subjects <65 years of age, patients >75 years [hazard ratio (HR), 4.7; 95% confidence interval (CI), 2.8-7.9; P < 0.001] and those 65-75 years (HR, 2.8; 95% CI, 1.7-4.8; P < 0.001) were at greater risk of death. Increased age was associated with higher total, cardiac, and non-cardiac mortality (all P

    View details for DOI 10.1093/europace/eun253

    View details for Web of Science ID 000260556300009

    View details for PubMedID 18818212

    View details for PubMedCentralID PMC2721725

  • The Irritable Heart JOURNAL OF HOSPITAL MEDICINE Turakhia, M. P., Grubb, B. P., Gregoratos, G. 2008; 3 (5): 423-429

    View details for DOI 10.1002/jhm.344

    View details for Web of Science ID 000260690300010

    View details for PubMedID 18951396

  • Knowledge and attitudes of primary care physicians in the management of patients at risk for cardiovascular events BMC FAMILY PRACTICE Doroodchi, H., Abdolrasulnia, M., Foster, J. A., Foster, E., Turakhia, M. P., Skelding, K. A., Sagar, K., Casebeer, L. L. 2008; 9

    Abstract

    Adherence to clinical practice guidelines for management of cardiovascular disease (CVD) is suboptimal. The purposes of this study were to identify practice patterns and barriers among U.S. general internists and family physicians in regard to cardiovascular risk management, and examine the association between physician characteristics and cardiovascular risk management.A case vignette survey focused on cardiovascular disease risk management was distributed to a random sample of 12,000 U.S. family physicians and general internists between November and December 2006.Responses from a total of 888 practicing primary care physicians who see 60 patients per week were used for analysis. In an asymptomatic patient at low risk for cardiovascular event, 28% of family physicians and 37% of general internists made guideline-based preventive choices for no antiplatelet therapy (p < .01). In a patient at high risk for cardiovascular event, 59% of family physicians and 56% of general internists identified the guideline-based goal for serum fasting LDL level (< 100 mg/dl). Guideline adherence was inversely related to years in practice and volume of patients seen. Cost of medications (87.7%), adherence to medications (74.1%), adequate time for counseling (55.7%), patient education tools (47.1%), knowledge and skills to recommend dietary changes (47.8%) and facilitate patient adherence (52.0%) were cited as significant barriers to CVD risk management.Despite the benefits demonstrated for managing cardiovascular risks, gaps remain in primary care practitioners' management of risks according to guideline recommendations. Innovative educational approaches that address barriers may facilitate the implementation of guideline-based recommendations in CVD risk management.

    View details for DOI 10.1186/1471-2296-9-42

    View details for Web of Science ID 000257836800001

    View details for PubMedID 18611255

  • Sudden cardiac death: Epidemiology, mechanisms, and therapy CURRENT PROBLEMS IN CARDIOLOGY Turakhia, M., Tseng, Z. H. 2007; 32 (9): 501-546

    Abstract

    Sudden cardiac death is a major public health problem affecting 500,000 patients annually in the United States alone. The major risk factor for sudden cardiac death is the presence of coronary artery disease, usually in the setting of reduced ejection fraction. Globally, the incidence is expected to rise sharply as the prevalence of coronary artery disease and heart failure continue to increase. However, sudden cardiac death is a heterogeneous condition and may be caused by acute ischemia, structural defects, myocardial scar, and/or genetic mutations. Sudden death may occur even in a grossly normal heart. Beta-blockers can reduce the risk of sudden cardiac death, while implantable cardioverter defibrillators are effective at terminating malignant arrhythmias. Ejection fraction remains the major criterion to stratify patients for defibrillator implantation but this strategy alone is insensitive and nonspecific. Novel clinical, electrophysiologic, and genetic markers have been identified that may increase precision in patient selection for primary prevention therapy. This review discusses the epidemiology, mechanisms, etiologies, therapies, treatment guidelines, and future directions in the management of sudden cardiac death.

    View details for DOI 10.1016/j.cpcardiol.2007.05.002

    View details for Web of Science ID 000249579000002

    View details for PubMedID 17723906

  • Impact of renal function on survival in patients with implantable cardioverter-defibrillators PACE-PACING AND CLINICAL ELECTROPHYSIOLOGY Turakhia, M. P., Varosy, P. D., Lee, K., Tseng, Z. H., Lee, R., Badhwar, N., Scheinman, M., Lee, B. K., Olgin, J. E. 2007; 30 (3): 377-384

    Abstract

    Although chronic renal insufficiency (CRI) is associated with increased cardiac and noncardiac mortality, there is limited data on the relationship between CRI and survival in patients with implantable cardioverter-defibrillators (ICDs), particularly across a wide range of renal function.We studied 507 consecutive patients receiving first-time ICDs from 1993-2003 at a single center. Preimplant serum creatinine measurements were used to determine glomerular filtration rate (GFR) and stage of chronic kidney disease (CKD). The primary outcome was time to death.During a mean follow-up of 4 years, all-cause mortality through completion of follow-up increased stepwise by GFR stage (I: 16%, II: 20%, III: 35%; IV: 40%; V: 50%; P < 0.001 for trend). After multivariate adjustment, CRI was independently associated with death (HR = 1.7, P = 0.02), as were a serum creatinine >or=2.0 mg/dL (HR 2.5, P = 0.003) and the presence of end-stage renal disease (HR 6.8; P < 0.001). For every 10-unit decrease in GFR, the adjusted hazard of death increased 12% (P = 0.04).The presence of CRI prior to implant is independently associated with increased mortality in patients receiving ICDs. The risk is proportional to the degree of renal dysfunction and is apparent even when GFR is only mildly reduced. Differences in mortality are observed within the first year of implant, and patients on dialysis are at highest risk. Because randomized trials of ICDs have not included large numbers of patients with moderate or severe renal disease, our findings may have important implications in prognosis and case selection of patients who otherwise meet current indications for ICD implantation.

    View details for Web of Science ID 000244886500011

    View details for PubMedID 17367357

  • Association of platelet count with residual thrombus in the myocardial infarct-related coronary artery among patients treated with fibrinolytic therapy for ST-segment elevation acute myocardial infarction AMERICAN JOURNAL OF CARDIOLOGY Turakhia, M. P., Murphy, S. A., Pinto, T. L., Antman, E. M., Giugliano, R. P., Cannon, C. P., Braunwald, E., Gibson, C. M. 2004; 94 (11): 1406-1410

    Abstract

    A higher platelet count is independently associated with the presence of residual thrombus in the infarct-related artery after administration of fibrinolytic therapy, even after multivariate adjustment.

    View details for DOI 10.1016/j.amjcard.2004.08.015

    View details for Web of Science ID 000225529600009

    View details for PubMedID 15566912

  • Sequential risk stratification using TIMI risk score and TIMI flow grade among patients treated with fibrinolytic therapy for ST-segment elevation acute myocardial infarction AMERICAN JOURNAL OF CARDIOLOGY Karmpaliotis, D., Turakhia, M. P., Kirtane, A., Murphy, S. A., Kosmidou, I., Morrow, D. A., Giugliano, R. P., Cannon, C. P., Antman, E. M., Braunwald, E., Gibson, C. M. 2004; 94 (9): 1113-1117

    Abstract

    In the setting of ST-segment elevation myocardial infarction (STEMI), the Thrombolysis In Myocardial Infarction (TIMI) risk score (TRS) and indexes of epicardial and myocardial perfusion are associated with mortality. The association between TRS at presentation and angiographic indexes of epicardial and myocardial perfusion after reperfusion therapy has not been investigated. We hypothesized that TRS, TIMI flow grade (TFG), and TIMI myocardial perfusion grade (TMPG) would provide independent prognostic information and that angiographic indexes of poor flow and perfusion would be associated with a higher TRS. TRS and angiographic data were evaluated in 3,801 patients from the TIMI 4, 10A, 10B, 14, 20, 23, and 24 trials. Within each TRS stratum (TRS 0 to 2, 3 to 4, >/=5), 30-day mortality increased stepwise among patients with impaired TFG at 60 minutes after fibrinolytic administration. In a multivariate model adjusting for the TRS strata, impaired TMPG (0/1) was independently associated with higher mortality (odds ratio 2.28, p = 0.018). In a multivariate model adjusting for the TFG and infarct location, the likelihood of impaired TMPG (0/1) was greater among intermediate-risk (TRS 3 to 4) and high-risk (TRS >/=5) patients than among low-risk (TRS 0 to 2) patients (odds ratio 1.43, p = 0.019 and 1.50, p = 0.055, respectively). Thus, impaired epicardial flow and myocardial perfusion are independently associated with increased 30-day mortality among patients identified by TRS as high risk, although there is no synergism between either TFG or TMPG and TRS. High TRS at presentation is associated with abnormal myocardial perfusion, even after adjusting for possible confounders.

    View details for DOI 10.1016/j.amjcard.2004.07.075

    View details for Web of Science ID 000224837500002

    View details for PubMedID 15518603

  • Association of the Fibonacci Cascade with the distribution of coronary artery lesions responsible for ST-segment elevation myocardial infarction AMERICAN JOURNAL OF CARDIOLOGY Gibson, C. M., Gibson, W. J., Murphy, S. A., Marble, S. J., McCabe, C. H., Turakhia, M. P., Kirtane, A. J., Karha, J., Aroesty, J. M., Giugliano, R. P., Antman, E. M. 2003; 92 (5): 595-597

    Abstract

    This is the first study to demonstrate the appearance of the Fibonacci Cascade within the distribution of coronary artery lesions in the human heart. The propensity for this ratio to appear in nature may also be because this ratio optimizes the efficiency of packing structures in a limited space in such a way that wasted space is minimized and the supply of energy or nutrients is optimized.

    View details for DOI 10.1016/S0002-9149(03)00731-8

    View details for Web of Science ID 000185060700020

    View details for PubMedID 12943884

  • Meperidine and alfentanil do not reduce the gain or maximum intensity of shivering ANESTHESIOLOGY Ikeda, T., Sessler, D. I., Tayefeh, F., Negishi, C., Turakhia, M., Marder, D., Bjorksten, A. R., Larson, M. D. 1998; 88 (4): 858-865

    Abstract

    Thermoregulatory shivering can be characterized by its threshold (triggering core temperature), gain (incremental intensity increase with further core temperature deviation), and maximum intensity. Meperidine (a combined mu- and kappa-agonist) treats shivering better than equianalgesic doses of pure mu-opioid agonists. Meperidine's special antishivering action is mediated, at least in part, by a disproportionate decrease in the shivering threshold. That is, meperidine decreases the shivering threshold twice as much as the vasoconstriction threshold, whereas alfentanil (a pure mu-agonist) decreases the vasoconstriction and shivering thresholds comparably. However, reductions in the gain or maximum shivering intensity might also contribute to the clinical efficacy of meperidine. Accordingly, we tested the hypothesis that meperidine reduces the gain and maximum intensity of shivering much more than alfentanil does.Ten volunteers were each studied on three separate days: (1) control (no drug); (2) a target total plasma meperidine concentration of 1.2 microg/ml; and (3) a target plasma alfentanil concentration of 0.2 microg/ml. Skin temperatures were maintained near 31 degrees C, and core temperatures were decreased by central-venous infusion of cold lactated Ringer's solution until maximum shivering intensity was observed. Shivering was evaluated using oxygen consumption and electromyography. A sustained increase in oxygen consumption identified the shivering threshold. The gain of shivering was calculated as the slope of the oxygen consumption versus core temperature regression, and as the slope of electromyographic intensity versus core temperature regression.Meperidine and alfentanil administration significantly decreased the shivering thresholds. However, neither meperidine nor alfentanil reduced the gain of shivering, as determined by either oxygen consumption or electromyography. Opioid administration also failed to significantly decrease the maximum intensity of shivering.The authors could not confirm the hypothesis that meperidine reduces the gain or maximum intensity of shivering more than alfentanil does. These results suggest that meperidine's special antishivering effect is primarily mediated by a disproportionate reduction in the shivering threshold.

    View details for Web of Science ID 000073024700003

    View details for PubMedID 9579492

  • Isoflurane alters shivering patterns and reduces maximum shivering intensity ANESTHESIOLOGY Ikeda, T., Kim, J. S., Sessler, D. I., Negishi, C., Turakhia, M., Jeffrey, R. 1998; 88 (4): 866-873

    Abstract

    Shivering can be characterized by its threshold (triggering core temperature), gain (incremental intensity increase with further core hypothermia), and maximum response intensity. Isoflurane produces a clonic muscular activity that is not a component of normal shivering. To the extent that clonic activity is superimposed on normal thermoregulatory shivering, the gain of shivering might be increased during isoflurane anesthesia. Conversely, volatile anesthetics decrease systemic oxygen consumption and peripherally inhibit skeletal muscle strength, which might limit maximum intensity despite central activation. The purpose of the present study was, therefore, to evaluate the effect of isoflurane shivering patterns and the gain and maximum intensity of shivering.Ten volunteers were each studied in two separate protocols: (1) control (no drug) and (2) 0.7% end-tidal isoflurane. On each day, the mean skin temperature was maintained at 31 degrees C. Core temperature was then reduced by infusion of cold fluid until shivering intensity no longer increased. The core temperature triggering the initial increase in oxygen consumption defined the shivering threshold. The gain of shivering was defined by the slope of the core temperature versus oxygen consumption regression. Pectoralis and quadriceps electromyography was used to evaluate anesthetic-induced facilitation of clonic (5-7 Hz) muscular activity.Isoflurane significantly decreased the shivering threshold from 36.4 +/- 0.3 to 34.2 +/- 0.8 degrees C. The increase in oxygen consumption was linear on the control day and was followed by sustained high-intensity activity. During isoflurane administration, shivering was characterized by bursts of intense shivering separated by quiescent periods. Isoflurane significantly increased the gain of shivering (as calculated from the initial increase), from -684 +/- 266 to -1483 +/- 752 ml x min(-1) x degrees C(-1). However, isoflurane significantly decreased the maximum intensity of shivering, from 706 +/- 144 to 489 +/- 80 ml/min. Relative electromyographic power in frequencies associated with clonus increased significantly when the volunteers were given isoflurane.These data indicate that isoflurane anesthesia markedly changes the overall pattern of shivering during progressive hypothermia from a linear increase to an unusual saw-tooth pattern. They further suggest that clonic muscular activity combines with shivering to increase the initial gain of shivering during isoflurane anesthesia, but that isoflurane peripherally inhibits the maximum expression of shivering.

    View details for Web of Science ID 000073024700004

    View details for PubMedID 9579493

  • Epidural anesthesia reduces and gain and maximum intensity of shivering ANESTHESIOLOGY Kim, J. S., Ikeda, T., Sessler, D. I., Turakhia, M., Jeffrey, R. 1998; 88 (4): 851-857

    Abstract

    Shivering can be characterized by its threshold (triggering core temperature), gain (incremental intensity increase), and maximum intensity. The gain of shivering might be preserved during epidural or spinal anesthesia if control mechanisms compensate for lower-body paralysis by augmenting the activity of upper-body muscles. Conversely, gain will be reduced approximately by half if the thermoregulatory system fails to compensate. Similarly, appropriate regulatory feedback might maintain maximum shivering intensity during regional anesthesia. Accordingly, the gain and maximum intensity of shivering during epidural anesthesia were determined.Seven volunteers participated on two randomly ordered study days. On one day (control), no anesthesia was administered; on the other, epidural anesthesia was maintained at a T8 sensory level. Shivering, at a mean skin temperature near 33 degrees C, was provoked by central-venous infusion of cold fluid; core cooling continued until shivering intensity no longer increased. Shivering was evaluated by systemic oxygen consumption and electromyography of two upper-body and two lower-body muscles. The core temperature triggering an increase in oxygen consumption identified the shivering threshold. The slopes of the oxygen consumption versus core temperature and electromyographic intensity versus core temperature regressions identified systemic and regional shivering gains, respectively.The shivering threshold was reduced by epidural anesthesia by approximately 0.4 degrees C, from 36.7 +/- 0.6 to 36.3 +/- 0.5 degrees C (means +/- SD; P < 0.05). Systemic gain, as determined by oxygen consumption, was reduced from -581 +/- 186 to -215 +/- 154 ml x min(-1) x degrees C(-1) (P < 0.01). Lower-body gain, as determined electromyographically, was essentially obliterated by paralysis during epidural anesthesia, decreasing from -0.73 +/- 0.85 to -0.04 +/- 0.06 intensity units/degrees C (P < 0.01). However, upper-body gain had no compensatory increase: -1.3 +/- 1.1 units/degrees C control versus 2.0 +/- 2.1 units/degrees C epidural. Maximum oxygen consumption was decreased by one third during epidural anesthesia: 607 +/- 82 versus 412 +/- 50 ml/min (P < 0.05).These results confirm that regional anesthesia reduces the shivering threshold. Epidural anesthesia reduced the gain of shivering by 63% because upper-body muscles failed to compensate for lower-body paralysis. The thermoregulatory system thus fails to recognize that regional anesthesia reduces metabolic heat production, instead responding as if lower-body muscular activity remained intact.

    View details for Web of Science ID 000073024700002

    View details for PubMedID 9579491

  • Postanesthetic vasoconstriction slows peripheral-to-core transfer of cutaneous heat, thereby isolating the core thermal compartment ANESTHESIA AND ANALGESIA Plattner, O., Ikeda, T., Sessler, D. I., Christensen, R., Turakhia, M. 1997; 85 (4): 899-906

    Abstract

    Forced-air warming during anesthesia increases core temperature comparably with and without thermoregulatory vasoconstriction. In contrast, postoperative forced-air warming may be no more effective than passive insulation. Nonthermoregulatory anesthesia-induced vasodilation may thus influence heat transfer. We compared postanesthetic core rewarming rates in volunteers given cotton blankets or forced air. Additionally, we compared increases in peripheral and core heat contents in the postanesthetic period with data previously acquired during anesthesia to determine how much vasomotion alters intercompartmental heat transfer. Six men were anesthetized and cooled passively until their core temperatures reached 34 degrees C. Anesthesia was then discontinued, and shivering was prevented by giving meperidine. On one day, the volunteers were covered with warmed blankets for 2 h; on the other, volunteers were warmed with forced air. Peripheral tissue heat contents were determined from intramuscular and skin thermocouples. Predicted changes in core temperature were calculated assuming that increases in body heat content were evenly distributed. Predicted changes were thus those that would be expected if vasomotor activity did not impair peripheral-to-core transfer of applied heat. These results were compared with those obtained previously in a similar study of anesthetized volunteers. Body heat content increased 159 +/- 35 kcal (mean +/- SD) more during forced-air than during blanket warming (P < 0.001). Both peripheral and core temperatures increased significantly faster during active warming: 3.3 +/- 0.7 degrees C and 1.1 +/- 0.4 degrees C, respectively. Nonetheless, predicted core temperature increase during forced-air warming exceeded the actual temperature increase by 0.8 +/- 0.3 degree C (P < 0.001). Vasoconstriction thus isolated core tissues from heat applied to the periphery, with the result that core heat content increased 32 +/- 12 kcal less than expected after 2 h of forced-air warming (P < 0.001). In contrast, predicted and actual core temperatures differed only slightly in the anesthetized volunteers previously studied. In contrast to four previous studies, our results indicate that forced-air warming increases core temperature faster than warm blankets. Postanesthetic vasoconstriction nonetheless impeded peripheral-to-core heat transfer, with the result that core temperatures in the two groups differed less than might be expected based on systemic heat balance estimates. Implications: Comparing intercompartmental heat flow in our previous and current studies suggests that anesthetic-induced vasodilation influences intercompartmental heat transfer and distribution of body heat more than thermoregulatory shunt vasomotion.

    View details for Web of Science ID A1997XY23200034

    View details for PubMedID 9322477

  • Rapid core-to-peripheral tissue heat transfer during cutaneous cooling ANESTHESIA AND ANALGESIA Plattner, O., Xiong, J. Y., Sessler, D. I., Schmied, H., Christensen, R., Turakhia, M., Dechert, M., Clough, D. 1996; 82 (5): 925-930

    Abstract

    Perioperative thermal manipulations are usually directed at the skin surface because methods of directly warming the core are invasive or ineffective. However, inadequate heat flow between peripheral and core compartments will decrease the rate at which core temperature changes. We therefore determined whether core hypothermia is delayed after initiation of surface cooling. Six volunteers were anesthetized with propofol and midazolam, and maintained under three layers of passive insulation for 2.5-4 h. Subsequently, the skin surface was cooled using forced air, 1000 L/min, at 10 degrees C. Isoflurane was added as necessary to maintain arteriovenous shunt vasodilation. Overall heat balance was determined from the difference between cutaneous heat loss (thermal flux transducers) and metabolic heat production (oxygen consumption). Average arm and leg (peripheral) tissue temperatures were determined from 19 intramuscular needle thermocouples, 10 skin temperatures, and "deep" foot temperature. Overall body heat content decreased approximately 234 kcal during 2.5 h of active cooling. Core temperature, which was nearly constant before active cooling, decreased approximately 1.3 degrees C/h. There was no delay between initiation of active cooling and the decrease in core temperature. Furthermore, peripheral (arm and leg) and core (trunk and head) tissue heat contents decreased at virtually the same rates: approximately 50 kcal/h and approximately 47 kcal/h, respectively. These data indicate that there is little restriction of heat flow between peripheral and core tissues in vasodilated, anesthetized subjects.

    View details for Web of Science ID A1996UH19500006

    View details for PubMedID 8610900