Bio

Bio


Dr. Chad Brodt specializes in the diagnosis and management of heart rhythm disorders. He performs catheter ablation to treat conditions of fast rhythms such as supraventricular tachycardia, atrial flutter, atrial fibrillation and ventricular tachycardia. In addition he performs implantation procedures of devices such as pacemakers for slow heart rhythms as well as defibrillators and biventricular pacing devices for individuals with heart failure or risk of fatal arrhythmias. He is currently interested in improving our understanding and utilization of low radiation techniques when performing electrophysiologic procedures. He is an active participant in the Stanford Arrhythmia Service's multiple ongoing clinical trials to further the advancement in this field. He collaborates directly with Stanford Cardiac Surgeons in pioneering new "hybrid" approaches to manage arrhythmias.

Clinical Focus


  • Clinical Cardiac Electrophysiology
  • Cardiovascular Disease

Academic Appointments


Professional Education


  • Fellowship:University of Miami Jackson Memorial Hospital Internal Med Residency (2014) FL
  • Board Certification: Clinical Cardiac Electrophysiology, American Board of Internal Medicine (2016)
  • Board Certification: Cardiovascular Disease, American Board of Internal Medicine (2015)
  • Fellowship:Stanford University Hospital (2015) CA
  • Board Certification: Internal Medicine, American Board of Internal Medicine (2012)
  • Residency:University of Miami Miller School of Medicine/Jackson Memorial Hospital (2011) FL
  • Medical Education:University of Sydney (2007) Australia
  • Board Certification, Clinical Cardiac Electrophysiology, American Board of Internal Medicine (2016)

Research & Scholarship

Clinical Trials


  • Pivotal Study Of A Dual Epicardial & Endocardial Procedure (DEEP) Approach Recruiting

    The objective of this study is to establish the safety and effectiveness of a dual epicardial and endocardial ablation procedure for patients presenting with Persistent Atrial Fibrillation or Longstanding Persistent Atrial Fibrillation

    View full details

  • Precision Event Monitoring for Patients With Heart Failure Using HeartLogic™ Recruiting

    The goal of the PREEMPT-HF study is to collect device and clinical event data to evaluate extended applications of the HeartLogicTM Heart Failure Diagnostic (HeartLogic) in a broad spectrum of heart failure (HF) patients with an implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy defibrillator (CRT-D). There are no primary safety and/or efficacy endpoints for this study. Heart failure (HF) is a complex clinical syndrome with high morbidity, mortality, and economic burden. Chronic HF is persistent, gradually progressive, and punctuated by episodes of acute worsening leading to hospitalizations. Therefore, there remains an unmet clinical need to slow the progression of HF and prevent hospitalizations. HeartLogicTM, available in Boston Scientific cardiac resynchronization therapy devices and defibrillators (CRT-Ds and ICDs), combines novel sensor parameters such as heart sounds and respiration with other measurements like thoracic impedance, heart rate, and activity into a HeartLogic Index for the early detection of worsening HF. However, there is limited data on the association of HeartLogic with the risk of HF readmissions and tachyarrhythmias, or for phenotyping the broad spectrum of HF patients.

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  • Low Fluoroscopy Afib Ablation Registry Not Recruiting

    Prospective data collection of patients undergoing Atrial Fibrillation Ablation.

    Stanford is currently not accepting patients for this trial. For more information, please contact Gerri O'Riordan, BSN RN, 650 7255597.

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Publications

All Publications


  • Safety and efficacy of zero fluoroscopy transseptal puncture with different approaches. Pacing and clinical electrophysiology : PACE Baykaner, T., Quadros, K., Thosani, A., Yasmeh, B., Mitra, R., Liu, E., Belden, W., Liu, Z., Costea, A., Brodt, C., Zei, P. 2019

    Abstract

    INTRODUCTION: AF ablation requires access to the left atrium (LA) via transseptal puncture (TP). TP is traditionally performed with fluoroscopic guidance. Use of intracardiac echocardiography (ICE) and 3D mapping allows for zero fluoroscopy TP.OBJECTIVE: To demonstrate safety and efficacy of zero fluoroscopy TP using multiple procedural approaches.METHODS: Patients undergoing AF ablation between 1/2015 and 11/2017 at 5 institutions were included. ICE and 3D mapping were used for sheath positioning and TP. Variable technical approaches were used across centers including placement of J wire in the SVC with ICE guidance followed by dragging down the transseptal sheath into the interatrial septum; or guiding the transseptal sheath directly to the interatrial septum by localizing the ablation catheter with 3D mapping and replacing it with the transseptal needle once in position. In patients with PM/ICD leads, pre/post-study device interrogation was performed.RESULTS: A total of 747 transseptal punctures were performed (646 patients, age 63.1±13.1, 67.5% male, LA volume index 34.5±15.8ml/m2 , EF 57.7±10.9%) with 100% success. No punctures required fluoroscopy. 2 pericardial effusions, 2 pericardial tamponades requiring pericardiocentesis and 1 TIA were observed during the overall ablation procedure, with a total complication rate of 0.7%. There were no other periprocedural complications related to TP, including intrathoracic bleeding, stroke or death both immediately following TP and within 30 days of the procedure. In patients with intracardiac devices, no device-related complications were observed.CONCLUSION: Transseptal puncture can be safely and effectively performed without the need for fluoroscopy. This article is protected by copyright. All rights reserved.

    View details for DOI 10.1111/pace.13841

    View details for PubMedID 31736095

  • Propagation velocity at atrial fibrillation sources: Go with the flow INTERNATIONAL JOURNAL OF CARDIOLOGY Rogers, A. J., Bhatia, N. K., Brodt, C. R., Narayan, S. M. 2019; 286: 76–77
  • Editorial: High density mapping of atrial fibrillation sources JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY Rogers, A. J., Bhatia, N. K., Brodt, C., Narayan, S. M. 2019; 30 (6): 964–65

    View details for DOI 10.1111/jce.13949

    View details for Web of Science ID 000472680300020

  • A novel pacing maneuver to verify the postpacing interval minus the tachycardia cycle length while adjusting for decremental conduction: Using "dual-chamber entrainment" for improved supraventricular tachycardia discrimination HEART RHYTHM Kaiser, D. W., Nasir, J. M., Liem, L., Brodt, C., Motonaga, K. S., Ceresnak, S. R., Turakhia, M. P., Dubin, A. M. 2019; 16 (5): 717–23
  • Propagation velocity at atrial fibrillation sources: Go with the flow. International journal of cardiology Rogers, A. J., Bhatia, N. K., Brodt, C. R., Narayan, S. M. 2019

    View details for PubMedID 30979605

  • SITES THAT CONTROL LARGER AREAS DURING ATRIAL FIBRILLATION MAY DETERMINE TERMINATION DURING ABLATION Bhatia, N. K., Hossainy, S., Rogers, A., Alhusseini, M., Brodt, C., Moosvi, N., Baykaner, T., Wang, P., Rappel, W., Narayan, S. ELSEVIER SCIENCE INC. 2019: 400
  • Editorial: High density mapping of atrial fibrillation sources. Journal of cardiovascular electrophysiology Rogers, A. J., Bhatia, N. K., Brodt, C., Narayan, S. M. 2019

    View details for PubMedID 31056801

  • Large-Scale Assessment of a Smartwatch to Identify Atrial Fibrillation. The New England journal of medicine Perez, M. V., Mahaffey, K. W., Hedlin, H., Rumsfeld, J. S., Garcia, A., Ferris, T., Balasubramanian, V., Russo, A. M., Rajmane, A., Cheung, L., Hung, G., Lee, J., Kowey, P., Talati, N., Nag, D., Gummidipundi, S. E., Beatty, A., Hills, M. T., Desai, S., Granger, C. B., Desai, M., Turakhia, M. P., Apple Heart Study Investigators, Perez, M. V., Turakhia, M. P., Lhamo, K., Smith, S., Berdichesky, M., Sharma, B., Mahaffey, K., Parizo, J., Olivier, C., Nguyen, M., Tallapalli, S., Kaur, R., Gardner, R., Hung, G., Mitchell, D., Olson, G., Datta, S., Gerenrot, D., Wang, X., McCoy, P., Satpathy, B., Jacobsen, H., Makovey, D., Martin, A., Perino, A., O'Brien, C., Gupta, A., Toruno, C., Waydo, S., Brouse, C., Dorfman, D., Stein, J., Huang, J., Patel, M., Fleischer, S., Doll, E., O'Reilly, M., Dedoshka, K., Chou, M., Daniel, H., Crowley, M., Martin, C., Kirby, T., Brumand, M., McCrystale, K., Haggerty, M., Newberger, J., Keen, D., Antall, P., Holbrook, K., Braly, A., Noone, G., Leathers, B., Montrose, A., Kosowsky, J., Lewis, D., Finkelmeier, J. R., Bemis, K., Mahaffey, K. W., Desai, M., Talati, N., Nag, D., Rajmane, A., Desai, S., Caldbeck, D., Cheung, L., Granger, C., Rumsfeld, J., Kowey, P. R., Hills, M. T., Russo, A., Rockhold, F., Albert, C., Alonso, A., Wruck, L., Friday, K., Wheeler, M., Brodt, C., Park, S., Rogers, A., Jones, R., Ouyang, D., Chang, L., Yen, A., Dong, J., Mamic, P., Cheng, P., Shah, R., Lorvidhaya, P. 2019; 381 (20): 1909–17

    Abstract

    BACKGROUND: Optical sensors on wearable devices can detect irregular pulses. The ability of a smartwatch application (app) to identify atrial fibrillation during typical use is unknown.METHODS: Participants without atrial fibrillation (as reported by the participants themselves) used a smartphone (Apple iPhone) app to consent to monitoring. If a smartwatch-based irregular pulse notification algorithm identified possible atrial fibrillation, a telemedicine visit was initiated and an electrocardiography (ECG) patch was mailed to the participant, to be worn for up to 7 days. Surveys were administered 90 days after notification of the irregular pulse and at the end of the study. The main objectives were to estimate the proportion of notified participants with atrial fibrillation shown on an ECG patch and the positive predictive value of irregular pulse intervals with a targeted confidence interval width of 0.10.RESULTS: We recruited 419,297 participants over 8 months. Over a median of 117 days of monitoring, 2161 participants (0.52%) received notifications of irregular pulse. Among the 450 participants who returned ECG patches containing data that could be analyzed - which had been applied, on average, 13 days after notification - atrial fibrillation was present in 34% (97.5% confidence interval [CI], 29 to 39) overall and in 35% (97.5% CI, 27 to 43) of participants 65 years of age or older. Among participants who were notified of an irregular pulse, the positive predictive value was 0.84 (95% CI, 0.76 to 0.92) for observing atrial fibrillation on the ECG simultaneously with a subsequent irregular pulse notification and 0.71 (97.5% CI, 0.69 to 0.74) for observing atrial fibrillation on the ECG simultaneously with a subsequent irregular tachogram. Of 1376 notified participants who returned a 90-day survey, 57% contacted health care providers outside the study. There were no reports of serious app-related adverse events.CONCLUSIONS: The probability of receiving an irregular pulse notification was low. Among participants who received notification of an irregular pulse, 34% had atrial fibrillation on subsequent ECG patch readings and 84% of notifications were concordant with atrial fibrillation. This siteless (no on-site visits were required for the participants), pragmatic study design provides a foundation for large-scale pragmatic studies in which outcomes or adherence can be reliably assessed with user-owned devices. (Funded by Apple; Apple Heart Study ClinicalTrials.gov number, NCT03335800.).

    View details for DOI 10.1056/NEJMoa1901183

    View details for PubMedID 31722151

  • Low-fluoroscopy atrial fibrillation ablation with contact force and ultrasound technologies: a learning curve. Pragmatic and observational research Zei, P. C., Hunter, T. D., Gache, L. M., O'Riordan, G., Baykaner, T., Brodt, C. R. 2019; 10: 1–7

    Abstract

    Background: Fluoroscopy exposure during catheter ablation is a health hazard to patients and operators. This study presents the results of implementing a low-fluoroscopy workflow using modern contact force (CF) technologies in paroxysmal atrial fibrillation (PAF) ablation.Methods: A fluoroscopy reduction workflow was implemented and subsequent catheter ablations for PAF were evaluated. After vascular access with ultrasound guidance, a THERMOCOOL SMARTTOUCH Catheter (ST) was advanced into the right atrium. The decapolar catheter was placed without fluoroscopy. A double-transseptal puncture was performed under intracardiac echocardiography guidance. ST and mapping catheters were advanced into the left atrium. A left atrial map was created, and pulmonary vein (PV) isolation was confirmed via entrance and exit block before and after the administration of isoproterenol or adenosine.Results: Forty-three patients underwent PAF ablation with fluoroscopy reduction workflow (mean age: 66±9 years; 70% male), performed by five operators. Acute success rate (PV isolation) was 96.5% of PVs. One case of pericardial effusion, not requiring intervention, was the only acute complication. Mean procedure time was 217±42 minutes. Mean fluoroscopy time was 2.3±3.0 minutes, with 97.7% of patients having < 10 minutes and 86.0% having < 5 minutes. A significant downward trend over time was observed, suggesting a rapid learning curve for fluoroscopy reduction. Freedom from any atrial arrhythmias without reablation was 80.0% after a mean follow-up of 12±3 months.Conclusion: Low fluoroscopy time is achievable with CF technologies after a short learning curve, without compromising patient safety or effectiveness.

    View details for PubMedID 30666175

  • Structurally-based electrical predictors of atrial arrhythmias. International journal of cardiology Rogers, A. J., Moosvi, N. F., Brodt, C. R., Narayan, S. M. 2018

    View details for PubMedID 30528625

  • A Novel Pacing Maneuver to Verify the Post-Pacing Interval Minus the Tachycardia Cycle Length While Adjusting for Decremental Conduction: Using 'Dual Chamber Entrainment' for Improved Supraventricular Tachycardia Discrimination. Heart rhythm Kaiser, D. W., Nasir, J. M., Liem, L. B., Brodt, C., Motonaga, K. S., Ceresnak, S. R., Turakhia, M. P., Dubin, A. M. 2018

    Abstract

    BACKGROUND: The post-pacing interval (PPI) minus the tachycardia cycle length (TCL) is frequently used to investigate tachycardias. However, a variety of issues (e.g. failure to entrain, decremental conduction, and oscillating TCLs) can make interpretation of the PPI-TCL challenging.OBJECTIVES: To investigate a novel maneuver to confirm the PPI-TCL value without using either the ventricular PPI or the TCL interval. To assess the ability of this maneuver to identify decremental conduction and differentiate supraventricular tachycardias.METHODS: We analyzed 77 intracardiac recordings from patients [age 25±20 years, 40 female] who underwent catheter ablation of AVNRT or orthodromic reciprocating tachycardia (ORT) with a concealed pathway. We calculated the PPI-TCL, the AH-corrected PPI-TCL, and estimated the PPI-TCL using "dual chamber entrainment" calculated as: [PPIV-TCL=Stim(AoV)+Stim(VoA)-PPIA].RESULTS: The PPI-TCL calculated by dual chamber entrainment highly correlated with the observed and AH-corrected PPI-TCL [R2=0.79 and 0.96, respectively, p<0.001]. A dual chamber entrainment PPI-TCL value of 80ms correctly differentiated all AVNRT from septal ORT cases, whereas the standard PPI-TCL and AH-corrected PPI-TCL methods were incorrect in 14% and 6% of cases, respectively. Dual chamber entrainment identified 3±10ms of additional decremental conduction beyond AH-prolongation, including four pathways with significant (>10ms) decrement.CONCLUSION: Dual chamber entrainment estimates the PPI-TCL value without using either the ventricular PPI or the TCL interval. This maneuver adjusts for all decremental conduction, including within concealed pathways, where a dual chamber entrainment PPI-TCL value >80ms favors AVNRT over ORT. This maneuver can be used to verify the observed PPI-TCL value in challenging cases.

    View details for PubMedID 30465902

  • Effects of Transendocardial Stem Cell Injection on Ventricular Proarrhythmia in Patients with Ischemic Cardiomyopathy: Results from the POSEIDON and TAC-HFT Trials. Stem cells translational medicine Ramireddy, A., Brodt, C. R., Mendizabal, A. M., DiFede, D. L., Healy, C., Goyal, V., Alansari, Y., Coffey, J. O., Viles-Gonzalez, J. F., Heldman, A. W., Goldberger, J. J., Myerburg, R. J., Hare, J. M., Mitrani, R. D. 2017; 6 (5): 1366–72

    Abstract

    Transendocardial stem cell injection in patients with ischemic cardiomyopathy (ICM) improves left ventricular function and structure but has ill-defined effects on ventricular arrhythmias. We hypothesized that mesenchymal stem cell (MSC) implantation is not proarrhythmic. Post hoc analyses were performed on ambulatory ECGs collected from the POSEIDON and TAC-HFT trials. Eighty-eight subjects (mean age 61 ± 10 years) with ICM (mean EF 32.2% ± 9.8%) received treatment with MSC (n = 48), Placebo (n = 21), or bone marrow mononuclear cells (BMC) (n = 19). Heart rate variability (HRV) and ventricular ectopy (VE) were evaluated over 12 months. VE did not change in any group following MSC implantation. However, in patients with ≥ 1 VE run (defined as ≥ 3 consecutive premature ventricular complexes in 24 hours) at baseline, there was a decrease in VE runs at 12 months in the MSC group (p = .01), but not in the placebo group (p = .07; intergroup comparison: p = .18). In a subset of the MSC group, HRV measures of standard deviation of normal intervals was 75 ± 30 msec at baseline and increased to 87 ± 32 msec (p =.02) at 12 months, and root mean square of intervals between successive complexes was 36 ± 30 msec and increased to 58.2 ± 50 msec (p = .01) at 12 months. In patients receiving MSCs, there was no evidence for ventricular proarrhythmia, manifested by sustained or nonsustained ventricular ectopy or worsened HRV. Signals of improvement in ventricular arrhythmias and HRV in the MSC group suggest a need for further studies of the antiarrhythmic potential of MSCs. Stem Cells Translational Medicine 2017;6:1366-1372.

    View details for DOI 10.1002/sctm.16-0328

    View details for PubMedID 28252842

    View details for PubMedCentralID PMC5442721

  • Temporal relationship of conduction system disease and ventricular dysfunction in LMNA cardiomyopathy. Journal of cardiac failure Brodt, C., Siegfried, J. D., Hofmeyer, M., Martel, J., Rampersaud, E., Li, D., Morales, A., Hershberger, R. E. 2013; 19 (4): 233–39

    Abstract

    LMNA cardiomyopathy presents with electrocardiogram (ECG) abnormalities, conduction system disease (CSD), and/or arrhythmias before the onset of dilated cardiomyopathy (DCM). Knowing the time interval between the onset of CSD and its progression to DCM would help to guide clinical care.We evaluated family members from 16 pedigrees previously identified to carry LMNA mutations for the ages of onset of ECG abnormalities, CSD, or arrhythmia and of left ventricular enlargement (LVE) and/or systolic dysfunction. Of 103 subjects, 64 carried their family LMNA mutation, and 51 (79%) had ECG abnormalities with a mean age of onset of 41.2 years (range 18-76). Ventricular dysfunction was observed in 26 with a mean age of onset of 47.6 years (range 28-82); at diagnosis 9 had systolic dysfunction but no LVE, 5 had LVE but no systolic dysfunction, and 11 had DCM. Of 16 subjects identified with ECG abnormalities who later developed ventricular dysfunction, the median ages of onset by log-rank analyses were 41 and 48 years, respectively.ECG abnormalities preceded DCM with a median difference of 7 years. Clinical surveillance should occur at least annually in those at risk for LMNA cardiomyopathy with any ECG findings.

    View details for DOI 10.1016/j.cardfail.2013.03.001

    View details for PubMedID 23582089

    View details for PubMedCentralID PMC3699310