Bio

Clinical Focus


  • Cardiology (Heart)
  • Interventional Cardiology

Academic Appointments


Professional Education


  • Medical Education:University of Minnesota (1992) MN
  • Residency:Stanford University School of Medicine (1995) CA
  • Fellowship:Stanford University School of Medicine (1998) CA
  • M.D., University of Minnesota, Medicine (1992)
  • S.B, M.I.T., Biology (1987)

Research & Scholarship

Current Research and Scholarly Interests


1. Use of GP IIb/IIIa inhibitors and other pharmacotherapy in the treatment of acute myocardial infarction
2. Novel treatments and devices for the treatment of acute myocardial infarction
3. Alcohol septal ablation for hypertrophic obstructive cardiomyopathy
4. Novel approaches to coronary revascularization
5. Closure devices for atrial septal defects and patent foramen ovale

Clinical Trials


  • FAME II - Fractional Flow Reserve (FFR) Guided Percutaneous Coronary Intervention (PCI) Plus Optimal Medical Treatment (OMT) Verses OMT Not Recruiting

    The overall purpose of the FAME II trial is to compare the clinical outcomes, safety and cost-effectiveness of FFR-guided PCI plus optimal medical treatment (OMT) versus OMT alone in patients with stable coronary artery disease.

    Stanford is currently not accepting patients for this trial. For more information, please contact Maria Perlas, (650) 723 - 2094.

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  • Renal Denervation in Patients With Uncontrolled Hypertension (SYMPLICITY HTN-3) Recruiting

    The Symplicity HTN-3 study is a, multi-center, prospective, single-blind, randomized, controlled study of the safety and effectiveness of renal denervation in subjects with uncontrolled hypertension. Bilateral renal denervation will be performed using the Symplicity Catheter - a percutaneous system that delivers radiofrequency (RF)energy through the luminal surface of the renal artery.

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  • PRESERVE-Zenith® Iliac Branch Clinical Study Recruiting

    The PRESERVE-Zenith® Iliac Branch Clinical Study is a clinical trial to study the safety and effectiveness of the Zenith® Branch Endovascular Graft-Iliac Bifurcation in combination with the Zenith® Connection Endovascular Stent/ConnectSX™/Atrium iCAST™ covered stent in the treatment of aorto-iliac and iliac aneurysms.

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  • TAXUS Libertē Post Approval Study Not Recruiting

    The TAXUS Libertē Post-Approval Study is an FDA-mandated prospective, multi-center study designed to collect real-world safety and clinical outcomes in approximately 4,200 patients receiving one or more TAXUS Liberté Paclitaxel-Eluting Stents and prasugrel as part of a dual antiplatelet therapy (DAPT) drug regimen. This study will also contribute patient data to an FDA-requested and industry-sponsored research study that will evaluate the optimal duration of dual antiplatelet therapy (DAPT Study).

    Stanford is currently not accepting patients for this trial. For more information, please contact Yvonne Strawa, (650) 498 - 7028.

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Teaching

2013-14 Courses


Publications

Journal Articles


  • Rationale and design of the TAXUS Liberte Post-Approval Study: Examination of patients receiving the TAXUS Liberte stent with concomitant prasugrel therapy in routine interventional cardiology practice AMERICAN HEART JOURNAL Garratt, K. N., Lee, D. P., Rose, E. M., Windle, K. J., Liao, H., Nwachuku, C. E., Winters, K. J., Bowman, T. S., Dawkins, K. D. 2012; 163 (2): 142-U226

    Abstract

    Observational studies of new coronary stents are necessary to assess performance in a variety of complex patient and lesion types. Furthermore, the optimal dose and duration of thienopyridine treatment is unclear, particularly in patients with complex clinical conditions. The TAXUS Libert? Post-Approval Study is designed to provide 5-year data on the TAXUS Liberté paclitaxel-eluting stent with concomitant prasugrel therapy in routine clinical practice and to contribute data to the DAPT study.The TAXUS Libert? Post-Approval Study is a prospective, multicenter, observational study. Enrollment of approximately 4,200 patients receiving ?1 TAXUS Liberté stents is planned. All patients without a contraindication will be prescribed prasugrel plus aspirin for 1 year. The 12-month primary end point of cardiac death or myocardial infarction in on-label stent patients will be compared with historical TAXUS Express stent data from the TAXUS ATLAS and TAXUS ARRIVE studies. Secondary clinical end points include stent thrombosis, all-cause death, stroke, revascularization, and bleeding in all patients. In addition, this study will be the first to evaluate prasugrel use in a routine practice setting (including 5 and 10 mg daily doses) and will contribute data to the DAPT Study, comparing 12 versus 30 months of dual antiplatelet therapy after drug-eluting stent placement.The TAXUS Libert? Post-Approval Study will be the first to provide long-term real-world data on use of the TAXUS Liberté Stent with prasugrel treatment. The study is currently enrolling, and primary end point data are expected in mid 2013.

    View details for DOI 10.1016/j.ahj.2011.11.002

    View details for Web of Science ID 000300226600003

    View details for PubMedID 22305829

  • On and Off: The Dilemma of Managing STEMI After Hours JOURNAL OF INVASIVE CARDIOLOGY Patel, S., Lee, D. P. 2009; 21 (10): 523-524

    View details for Web of Science ID 000284807100008

    View details for PubMedID 19805839

  • Risk factors for the development of retroperitoneal hematoma after percutaneous coronary intervention in the era of glycoprotein IIb/IIIa inhibitors and vascular closure devices JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Farouque, H. M., Tremmel, J. A., Shabari, F. R., Aggarwal, M., Fearon, W. F., Ng, M. K., Rezaee, M., Yeung, A. C., Lee, D. P. 2005; 45 (3): 363-368

    Abstract

    We sought to determine the incidence, clinical features, and risk factors for retroperitoneal hematoma (RPH) after percutaneous coronary intervention (PCI).Little is known about the clinical features, outcomes, and determinants of this serious complication in the contemporary era of PCI.A retrospective analysis yielded 26 cases of RPH out of 3,508 consecutive patients undergoing PCI between January 2000 and January 2004. Cases were compared with a randomly selected sample of 50 control subjects without RPH.The incidence of RPH was 0.74%. Features of RPH included abdominal pain (42%), groin pain (46%), back pain (23%), diaphoresis (58%), bradycardia (31%), and hypotension (92%). The mean systolic blood pressure nadir was 75 mm Hg. The hematocrit dropped by 11.5 +/- 5.1 points from baseline in RPH patients, as compared with 2.3 +/- 3.3 points in controls (p < 0.0001). The mean hospital stay was longer in RPH patients (2.9 +/- 3.8 days vs. 1.7 +/- 1.5 days, p = 0.06). The following variables were found to be independent predictors of RPH: female gender (odds ratio [OR] 5.4, p = 0.005), low body surface area (BSA <1.73 m(2); OR 7.1, p = 0.008), and higher femoral artery puncture (OR 5.3, p = 0.013). There was no association between RPH and arterial sheath size, use of glycoprotein IIb/IIIa inhibitors, or deployment of a vascular closure device.Female gender, low BSA, and higher femoral artery puncture are significant risk factors for RPH. Awareness of the determinants and clinical features of RPH may aid in prevention, early recognition, and prompt treatment.

    View details for DOI 10.1016/j.jacc.2004.10.042

    View details for Web of Science ID 000226673400006

    View details for PubMedID 15680713

  • Most accurate definition of a high femoral artery puncture: Aiming to better predict retroperitoneal hematoma in percutaneous coronary intervention CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS Tremmel, J. A., Tibayan, Y. D., O'Loughlin, A. J., Chan, T., Fearon, W. F., Yeung, A. C., Lee, D. P. 2012; 80 (1): 37-42

    Abstract

    Retroperitoneal hematoma (RPH) increases morbidity and mortality in percutaneous coronary intervention (PCI). High femoral arteriotomy is an independent predictor of RPH, but the optimal angiographic criterion for defining a high puncture is unknown.We retrospectively identified 557 consecutive PCI cases with femoral angiograms. Arteriotomy sites were categorized as high based on three angiographic criteria: at or above the proximal third of the femoral head (criterion A), at or above the most inferior border of the inferior epigastric artery (criterion B), and at or above the origin of the inferior epigastric artery (criterion C). Cases of RPH were then identified.Of the 557 PCI patients, 26 had a high femoral arteriotomy by criterion A, 17 by criterion B, and 6 by criterion C. Among these patients with a high arteriotomy, RPH occurred in four with criterion A, in three with criterion B, and in one with criterion C. Of the three criteria, criterion A most strongly correlated with RPH (odds ratio [OR] 96, 95% confidence interval [CI] 10.3-898.4; p < 0.0001) compared with criterion B (OR 58, 95% CI 8.9 to 372.6; p < 0.0001) or C (OR 27, 95% CI 2.6 to 290.1; p = 0.053). All criteria had high specificity (A, 96%; B, 97%; C, 99%), but the sensitivity was higher with criterion A (80%) than criterion B (60%) or C (20%), and statistically, the use of criterion A led to the most accurate risk-stratification for RPH (A, ? = 0.79; B, ? = 0.59; C, ? = 0.19).Among the three common definitions of high arteriotomy, femoral artery puncture at or above the proximal third of the femoral head is the landmark that most accurately risk stratifies PCI patients for development of RPH.

    View details for DOI 10.1002/ccd.23175

    View details for Web of Science ID 000305692100005

    View details for PubMedID 22511409

  • Cardiac Paraganglioma: Diagnostic and Surgical Challenges JOURNAL OF CARDIAC SURGERY Huo, J. L., Choi, J. C., DeLuna, A., Lee, D., Fleischmann, D., Berry, G. J., Deuse, T., Haddad, F. 2012; 27 (2): 178-182

    Abstract

    Primary cardiac paragangliomas are rare extra-adrenal tumors. Though they account for less than 1% of all primary cardiac tumors, they are considerable sources of morbidity and mortality. In this case review, we discuss the challenges associated with the diagnosis and management of cardiac paragangliomas.

    View details for DOI 10.1111/j.1540-8191.2011.01378.x

    View details for Web of Science ID 000302172800009

    View details for PubMedID 22273468

  • Coil Embolization of a Left Circumflex Feeder Branch in a Patient With a Mediastinal Paraganglioma JACC-CARDIOVASCULAR INTERVENTIONS Ho, M. Y., Fleischmann, D., Forrester, M. D., Lee, D. P. 2011; 4 (12): 1345-1346

    View details for DOI 10.1016/j.jcin.2011.06.021

    View details for Web of Science ID 000298830500011

    View details for PubMedID 22192376

  • Comparison of the Frequency of Coronary Artery Disease in Alcohol-Related Versus Non-Alcohol-Related Endstage Liver Disease AMERICAN JOURNAL OF CARDIOLOGY Patel, S., Kiefer, T. L., Ahmed, A., Ali, Z. A., Tremmel, J. A., Lee, D. P., Yeung, A. C., Fearon, W. F. 2011; 108 (11): 1552-1555

    Abstract

    There are conflicting data as to the prevalence of coronary artery disease (CAD) in patients with end-stage liver disease (ESLD) being assessed for liver transplantation (LT). The aims of this study were to compare the prevalence of CAD in patients with alcohol-related versus non-alcohol-related ESLD and to assess the diagnostic utility of dobutamine stress echocardiography (DSE) in predicting angiographically important CAD. Consecutive patients with ESLD being assessed for LT (n = 420, mean age 56 ± 8 years) were identified and divided into groups of those with alcohol-related ESLD (n = 125) and non-alcohol-related ESLD (n = 295). Demographic characteristics, CAD risk factors, results of DSE, and coronary angiographic characteristics were recorded. There were no significant differences in age or CAD risk factors between groups. The incidence of severe CAD (>70% diameter stenosis) was 2% in the alcohol-related ESLD group and 13% in the non-alcohol-related ESLD group (p <0.005). In the 2 groups, the presence of ?1 CAD risk factor was associated with significant CAD (p <0.05 for all). Absence of cardiac risk factors was highly predictive in ruling out angiographically significant disease (negative predictive value 100% for alcohol-related ESLD and 97% for non-alcohol-related ESLD). DSE was performed in 205 patients. In the 2 groups, DSE had poor predictive value for diagnosing significant CAD but was useful in ruling out patients without significant disease (negative predictive value 89% for alcohol-related ESLD and 80% for non-alcohol-related ESLD). In conclusion, there was a significantly lower prevalence of severe CAD in patients with alcohol-related ESLD. These findings suggest that invasive coronary angiography may not be necessary in this subgroup, particularly in the absence of CAD risk factors and negative results on DSE.

    View details for DOI 10.1016/j.amjcard.2011.07.013

    View details for Web of Science ID 000297880000006

    View details for PubMedID 21890080

  • Comparison of Drug-Eluting Versus Bare Metal Stents in Cardiac Allograft Vasculopathy AMERICAN JOURNAL OF CARDIOLOGY Tremmel, J. A., Ng, M. K., Ikeno, F., Hunt, S. A., Lee, D. P., Yeung, A. C., Fearon, W. F. 2011; 108 (5): 665-668

    Abstract

    Although not a definitive treatment, percutaneous coronary intervention offers a palliative benefit to patients with cardiac allograft vasculopathy. Given the superior outcomes with drug-eluting stents (DESs) over bare metal stents (BMSs) in native coronary artery disease, similar improvements might be expected in transplant patients; however, the results have been mixed. Consecutive cardiac transplantation recipients at a single center receiving a stent for de novo cardiac allograft vasculopathy from 1997 to 2009 were retrospectively analyzed according to receipt of a DES versus a BMS. The angiographic and clinical outcomes were subsequently evaluated at 1 year. The baseline clinical and procedural characteristics were similar among those receiving DESs (n = 18) and BMSs (n = 16). Quantitative coronary angiography revealed no difference in the reference diameter, lesion length, or pre-/postprocedural minimal luminal diameter. At the 12-month angiographic follow-up visit, the mean lumen loss was significantly lower in the DES group than in the BMS group (0.19 ± 0.73 mm vs 0.76 ± 0.97 mm, p = 0.02). The DES group also had a lower rate of in-stent restenosis (12.5% vs 33%, p = 0.18), as well as a significantly lower rate of target lesion revascularization (0% vs 19%, p = 0.03). At 1 year, DESs were associated with a lower composite rate of cardiac death and nonfatal myocardial infarction (12% vs 38%, p = 0.04). In conclusion, DESs are safe and effective in the suppression of neointimal hyperplasia after percutaneous coronary intervention for cardiac allograft vasculopathy, resulting in significantly lower rates of late lumen loss and target lesion revascularization, as well as a reduced combined rate of cardiac death and nonfatal myocardial infarction.

    View details for DOI 10.1016/j.amjcard.2011.04.014

    View details for Web of Science ID 000294751000009

    View details for PubMedID 21684511

  • Managing Pre-Hospital ECGs: The Devil Is in the Details JOURNAL OF INVASIVE CARDIOLOGY Ko, J., Lee, D. P. 2010; 22 (11): 526-526

    View details for Web of Science ID 000284808400006

    View details for PubMedID 21041848

  • Biopsy of Cardiac Masses Using a Stabilized Intracardiac Echocardiography-guided System JOURNAL OF VASCULAR AND INTERVENTIONAL RADIOLOGY Sze, D. Y., Lee, D. P., Hofmann, L. V., Petersen, B. 2008; 19 (11): 1662-1667

    Abstract

    Biopsy of a cardiac mass remains a difficult and risky procedure. Successful sampling of target tissue is hampered by continuous cardiac motion and blood flow. Because the surrounding tissues are vascular, complications can include hemorrhage, tamponade, arrhythmia, embolization, and death. Conventional imaging modalities are of limited utility in this dynamic environment. The present report describes the use of the instrumentation system originally designed for creation of direct portocaval shunts with intracardiac echocardiography imaging to perform core biopsies of cardiac and juxtacardiac masses in six patients. There were no hemorrhagic complications, and pathologic diagnoses were obtained in five of six cases.

    View details for DOI 10.1016/j.jvir.2008.08.001

    View details for Web of Science ID 000260694700020

    View details for PubMedID 18818096

  • Effect of rapamycin therapy on coronary artery physiology early after cardiac transplantation AMERICAN HEART JOURNAL Sinha, S. S., Pham, M. X., Vagelos, R. H., Perlroth, M. G., Hunt, S. A., Lee, D. P., Valantine, H. A., Yeung, A. C., Fearon, W. F. 2008; 155 (5)

    Abstract

    Rapamycin has been shown to reduce anatomical evidence of cardiac allograft vasculopathy, but its effect on coronary artery physiology is unknown.Twenty-seven patients without angiographic evidence of coronary artery disease underwent measurement of fractional flow reserve (FFR), coronary flow reserve (CFR), and the index of microcirculatory resistance (IMR) within 8 weeks and then 1 year after transplantation using a pressure sensor/thermistor-tipped guidewire. Measurements were compared between consecutive patients who were on rapamycin for at least 3 months during the first year after transplantation (rapamycin group, n = 9) and a comparable group on mycophenolate mofetil (MMF) instead (MMF group, n = 18).At baseline, there was no significant difference in FFR, CFR, or IMR between the 2 groups. At 1 year, FFR declined significantly in the MMF group (0.87 +/- 0.06 to 0.82 +/- 0.06, P = .009) but did not change in the rapamycin group (0.91 +/- 0.05 to 0.89 +/- 0.04, P = .33). Coronary flow reserve and IMR did not change significantly in the MMF group (3.1 +/- 1.7 to 3.2 +/- 1.0, P = .76; and 27.5 +/- 18.1 to 19.1 +/- 7.6, P = .10, respectively) but improved significantly in the rapamycin group (2.3 +/- 0.8 to 3.8 +/- 1.4, P < .03; and 27.0 +/- 11.5 to 17.6 +/- 7.5, P < .03, respectively). Multivariate regression analysis revealed that rapamycin therapy was an independent predictor of CFR and FFR at 1 year after transplantation.Early after cardiac transplantation, rapamycin therapy is associated with improved coronary artery physiology involving both the epicardial vessel and the microvasculature.

    View details for DOI 10.1016/j.ahj.2008.02.004

    View details for Web of Science ID 000256001500014

    View details for PubMedID 18440337

  • Predictive value of the index of microcirculatory resistance in patients with ST-segment elevation myocardial infarction JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Fearon, W. F., Shah, M., Ng, M., Brinton, T., Wilson, A., Trernmel, J. A., Schnittger, I., Lee, D. P., Vagelos, R. H., Fitzgerald, P. J., Yock, P. G., Yeung, A. C. 2008; 51 (5): 560-565

    Abstract

    The objective of this study is to evaluate the predictive value of the index of microcirculatory resistance (IMR) in patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI).Despite adequate epicardial artery reperfusion, a number of patients with STEMI have a poor prognosis because of microvascular damage. Assessing the status of the microvasculature in this setting remains challenging.In 29 patients after primary PCI for STEMI, IMR was measured with a pressure sensor/thermistor-tipped guidewire. The Thrombolysis In Myocardial Infarction (TIMI) myocardial perfusion grade, TIMI frame count, coronary flow reserve, and ST-segment resolution were also recorded.The IMR correlated significantly with the peak creatinine kinase (CK) (R = 0.61, p = 0.0005) while the other measures of microvascular dysfunction did not. In patients with an IMR greater than the median value of 32 U, the peak CK was significantly higher compared with those having values 32 U compared with

    View details for DOI 10.1016/j.jacc.2007.08.062

    View details for Web of Science ID 000252908600007

    View details for PubMedID 18237685

  • A Cagey Proposition JOURNAL OF INVASIVE CARDIOLOGY Ho, Y., Lee, D. P. 2008; 20 (1): 28-28

    View details for Web of Science ID 000207734600007

    View details for PubMedID 18174615

  • Changes in coronary anatomy and physiology after heart transplantation AMERICAN JOURNAL OF CARDIOLOGY Hirohata, A., Nakamura, M., Waseda, K., Honda, Y., Lee, D. P., Vagelos, R. H., Hunt, S. A., Valantine, H. A., Yock, P. G., Fitzgerald, P. J., Yeung, A. C., Fearon, W. F. 2007; 99 (11): 1603-1607

    Abstract

    Cardiac allograft vasculopathy (CAV) is a progressive process involving the epicardial and microvascular coronary systems. The timing of the development of abnormalities in these 2 compartments and the correlation between changes in physiology and anatomy are undefined. The invasive evaluation of coronary artery anatomy and physiology with intravascular ultrasound, fractional flow reserve, coronary flow reserve, and the index of microcirculatory resistance (IMR) was performed in the left anterior descending coronary artery during 151 angiographic evaluations of asymptomatic heart transplant recipients from 0 to >5 years after heart transplantation (HT). There was no angiographic evidence of significant CAV, but during the first year after HT, fractional flow reserve decreased significantly (0.89 +/- 0.06 vs 0.85 +/- 0.07, p = 0.001), and percentage plaque volume derived by intravascular ultrasound increased significantly (15.6 +/- 7.7% to 22.5 +/- 12.3%, p = 0.0002), resulting in a significant inverse correlation between epicardial physiology and anatomy (r = -0.58, p <0.0001). The IMR was lower in these patients compared with those > or =2 years after HT (24.1 +/- 14.3 vs 29.4 +/- 18.8 units, p = 0.05), suggesting later spread of CAV to the microvasculature. As the IMR increased, fractional flow reserve increased (0.86 +/- 0.06 to 0.90 +/- 0.06, p = 0.0035 comparing recipients with IMRs < or =20 to those with IMRs > or =40), despite no difference in percentage plaque volume (21.0 +/- 11.2% vs 20.5 +/- 10.5%, p = NS). In conclusion, early after HT, anatomic and physiologic evidence of epicardial CAV was found. Later after HT, the physiologic effect of epicardial CAV may be less, because of increased microvascular dysfunction.

    View details for DOI 10.1016/j.amjcard.2007.01.039

    View details for Web of Science ID 000247121700024

    View details for PubMedID 17531589

  • Spontaneous coronary artery dissection in a woman with depression without coronary atherosclerotic risk factors. journal of invasive cardiology Ho, Y., Koizumi, T., Lee, D. P. 2007; 19 (6): E166-8

    View details for PubMedID 17541140

  • Recurrent spontaneous coronary artery dissection with transient left ventricular systolic dysfunction. International journal of cardiology Ardehali, R., Brinton, T. J., Wilson, A. M., Gradman, M., Vagelos, R. H., Lee, D. P. 2007; 116 (2): e48-50

    Abstract

    Spontaneous coronary artery dissection (SCAD) is a potentially life-threatening entity with a variety of clinical presentations. We report a patient who presented with chest pain and angiographic evidence of coronary dissection. Due to the rapid resolution of symptoms and benign-appearing nature of the dissection, no intervention was pursued and the patient was maintained on medical therapy. She represented 2 days later with substernal chest pain, dynamic EKG changes, positive cardiac biomarkers and a transient depression of her left ventricular function.

    View details for PubMedID 16930750

  • Percutaneous translurninal coronary angioplasty in a two-month old with coronary stenosis presenting as congenital cardiomyopathy: Acute results and intermediate follow-up CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS Cheng, C. W., Lee, D. P., Rosenthal, D. N., Feinstein, J. A. 2006; 68 (4): 632-636

    Abstract

    Congenital or nonsurgically acquired obstructive coronary artery disease in infancy is exceedingly rare, and previous reports of catheter-based therapies in very young patients have been solely in patients having undergone arterial switch or other cardiovascular surgical procedures. We describe a previously unreported cause for ventricular dysfunction and heart failure in an infant, isolated congenital circumflex coronary artery stenosis, and successful treatment with percutaneous transluminal coronary angioplasty. Technical considerations, immediate results, and 3-year follow-up are provided.

    View details for DOI 10.1002/ccd.20750

    View details for Web of Science ID 000241048000023

    View details for PubMedID 16969876

  • Cutting balloon inflation for drug-eluting stent underexpansion due to unrecognized coronary arterial calcification. Cardiovascular revascularization medicine : including molecular interventions Wilson, A., Ardehali, R., Brinton, T. J., Yeung, A. C., Lee, D. P. 2006; 7 (3): 185-188

    Abstract

    Unrecognized calcification is a cause of stent underexpansion which significantly increases the subsequent risks of restenosis and/or stent thrombosis. We describe the use of cutting balloon inflation within the implanted stent which overcame calcific restraint unresponsive to high pressure inflations with non-compliant balloons.

    View details for PubMedID 16945827

  • Discordant changes in epicardial and microvascular coronary physiology after cardiac transplantation: Physiologic investigation for transplant arteriopathy II (PITA II) study JOURNAL OF HEART AND LUNG TRANSPLANTATION Fearon, W. F., Hirohata, A., Nakamura, M., Luikart, H., Lee, D. P., Vagelos, R. H., Hunt, S. A., Valantine, H. A., Fitzgerald, P. J., Yock, P. G., Yeung, A. C. 2006; 25 (7): 765-771

    Abstract

    Investigating changes in coronary physiology that occur after cardiac transplantation has been challenging. Simultaneous and independent assessment of the epicardial artery by measuring fractional flow reserve (FFR) and of the microvasculature by calculating the index of microvascular resistance (IMR) with a single coronary pressure wire may be useful.Twenty-five asymptomatic patients with normal coronary angiograms underwent FFR, thermodilution-derived IMR and coronary flow reserve (CFR) and intravascular ultrasound (IVUS) evaluation soon after cardiac transplantation and 1 year later.FFR significantly worsened (0.90 +/- 0.05 at baseline to 0.85 +/- 0.06 at 1 year, p = 0.004). FFR correlated strongly with percent plaque volume as measured by IVUS (r = -0.58, p < 0.0001). IMR improved significantly (29.2 +/- 15.9 at baseline to 19.3 +/- 7.6 units at 1 year, p = 0.007). CFR increased, but not significantly (2.6 +/- 1.4 at baseline to 3.2 +/- 1.2 at 1 year, p = not significant). Diabetes and donor heart ischemic time independently predicted baseline IMR. Treatment with rapamycin independently predicted FFR at 1 year.New coronary physiologic measures, FFR and IMR, show that epicardial artery physiology worsens and correlates with anatomic changes, whereas microvascular physiology improves during the first year after cardiac transplantation. CFR, the traditional method for evaluating coronary circulatory physiology, did not identify these changes.

    View details for DOI 10.1016/j.healun.2006.03.003

    View details for Web of Science ID 000239019700003

    View details for PubMedID 16818118

  • Identification and treatment of vulnerable plaque. Reviews in cardiovascular medicine Nakamura, M., Lee, D. P., Yeung, A. C. 2004; 5: S22-33

    Abstract

    It is now well recognized that the rupture of vulnerable plaque, which consists of an atheromatous plaque core covered by a thin fibrous cap with ongoing inflammation, is a major cause of thrombus formation leading to the development of acute coronary syndrome. Several diagnostic techniques, including vascular imaging and serologic markers, are clinically available or currently under investigation for the detection of vulnerable plaque. A combination of several diagnostic modalities might allow effective screening of individuals at high risk for future cardiovascular events. Plaque stabilization with pharmacologic interventions--statins, beta-blockers, and angiotensin-converting enzyme inhibitors--might effectively prevent the development of acute coronary syndromes caused by plaque disruption.

    View details for PubMedID 15184831

  • Simultaneous assessment of fractional and coronary flow reserves in cardiac transplant recipients - Physiologic investigation for transplant arteriopathy (PITA study) CIRCULATION Fearon, W. F., Nakamura, M., Lee, D. P., Rezaee, M., Vagelos, R. H., Hunt, S. A., Fitzgerald, P. J., Yock, P. G., Yeung, A. C. 2003; 108 (13): 1605-1610

    Abstract

    The utility of measuring fractional flow reserve (FFR) to assess cardiac transplant arteriopathy has not been evaluated. Measuring coronary flow reserve (CFR) as well as FFR could add information about the microcirculation, but until recently, this has required two coronary wires. We evaluated a new method for simultaneously measuring FFR and CFR with a single wire to investigate transplant arteriopathy.In 53 cases of asymptomatic cardiac transplant recipients without angiographically significant coronary disease, FFR and thermodilution-derived CFR (CFRthermo) were measured simultaneously with the same coronary pressure wire in the left anterior descending artery and compared with volumetric intravascular ultrasound (IVUS) imaging. The average FFR was 0.88+/-0.07; in 75% of cases, the FFR was less than the normal threshold of 0.94; and in 15% of cases, the FFR was < or =0.80, the upper boundary of the gray zone of the ischemic threshold. There was a significant inverse correlation between FFR and IVUS-derived measures of plaque burden, including percent plaque volume (r=0.55, P<0.0001). The average CFRthermo was 2.5+/-1.2; in 47% of cases, CFRthermo was < or =2.0. In 14%, the FFR was normal (> or =0.94) and the CFR was abnormal (<2.0), suggesting predominant microcirculatory dysfunction.FFR correlates with IVUS findings and is abnormal in a significant proportion of asymptomatic cardiac transplant patients with normal angiograms. Simultaneous measurement of CFR with the same pressure wire, with the use of a novel coronary thermodilution technique, is feasible and adds information to the physiological evaluation of these patients.

    View details for DOI 10.1161/01.CIR.0000091116.84926.6F

    View details for Web of Science ID 000185624500027

    View details for PubMedID 12963639

  • Late incomplete apposition with excessive remodeling of the stented coronary artery following intravascular brachytherapy AMERICAN JOURNAL OF CARDIOLOGY Okura, H., Lee, D. P., Lo, S., Yeung, A. C., Honda, Y., Waksman, R., Kaluza, G. L., Ali, N. M., Bonneau, H. N., Yock, P. G., Raizner, A. E., Mintz, G. S., Fitzgerald, P. J. 2003; 92 (5): 587-590

    Abstract

    Intravascular brachytherapy may cause "exaggerated" vessel remodeling with late incomplete apposition in segments that have little disease, which are exposed to higher radiation doses. The long-term clinical impact of this finding is unclear.

    View details for DOI 10.1016/S0002-9149(03)00728-8

    View details for Web of Science ID 000185060700017

    View details for PubMedID 12943881

  • Effect of a change in gender on coronary arterial size - A longitudinal intravascular ultrasound study in transplanted hearts JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Herity, N. A., Lo, S., Lee, D. P., Ward, M. R., Filardo, S. D., Yock, P. G., Fitzgerald, P. J., Hunt, S. A., Yeung, A. C. 2003; 41 (9): 1539-1546

    Abstract

    We sought to document whether a physiologic change in gender has any effect on coronary arterial size.The coronary arteries are smaller in women, even after correction for body surface area (BSA). These differences may contribute to adverse clinical outcomes after coronary artery bypass graft surgery and myocardial infarction in women. In male and female transsexuals, pharmacologic doses of estrogens and androgens significantly influence vascular diameter. Thus, gender differences in the coronary vasculature may be a reflection of the hormonal environment.In 86 patients who had undergone orthotopic heart transplantation, serial intravascular ultrasound studies of the proximal left anterior descending coronary artery (LAD) were analyzed. Changes in vessel area (VA) over the first or second post-transplant year were recorded, and comparisons were made between donor hearts that were transplanted in a patient of the same gender and those that were transplanted in a patient of the opposite gender.Vessel area of the proximal LAD increased over time in all patient groups. In hearts transplanted within the same gender and in male donor hearts transplanted to female recipients, the change was small and not significant. However, in hearts transplanted from female donors to male recipients, there was a substantial and highly significant increase in LAD VA (median 16.13 to 17.88 mm(2); p = 0.01). This increase was not explained by confounding due to changes in BSA or left ventricular wall thickness.This pattern of arterial remodeling early after heart transplantation supports a link between host gender and coronary arterial size.

    View details for DOI 10.1016/S0735-1097(03)00246-8

    View details for Web of Science ID 000182631800019

    View details for PubMedID 12742295

  • Cost-effectiveness of measuring fractional flow reserve to guide coronary interventions AMERICAN HEART JOURNAL Fearon, W. F., Yeung, A. C., Lee, D. P., Yock, P. G., Heidenreich, P. A. 2003; 145 (5): 882-887

    Abstract

    Most patients come to the catheterization laboratory without prior functional tests, which makes the cost-effective treatment of patients with intermediate coronary lesions a practical challenge.We developed a decision model to compare the long-term costs and benefits of 3 strategies for treating patients with an intermediate coronary lesion and no prior functional study: 1) deferring the decision for percutaneous coronary intervention (PCI) to obtain a nuclear stress imaging study (NUC strategy); 2) measuring fractional flow reserve (FFR) at the time of angiography to help guide the decision for PCI (FFR strategy); and 3) stenting all intermediate lesions (STENT strategy). On the basis of the literature, we estimated that 40% of intermediate lesions would produce ischemia, 70% of patients treated with PCI and 30% of patients treated medically would be free of angina after 4 years, and the quality-of-life adjustment for living with angina was 0.9 (1.0 = perfect health). We estimated the cost of FFR to be 761 dollars, the cost of nuclear stress imaging to be 1093 dollars, and the cost of medical treatment for angina to be 1775 dollars per year. The extra cost of splitting the angiogram and PCI as dictated by the NUC strategy was 3886 dollars by use of hospital cost-accounting data. Sensitivity and threshold analyses were performed to determine which variables affected our results.The FFR strategy saved 1795 dollars per patient compared with the NUC strategy and 3830 dollars compared with the STENT strategy. Quality-adjusted life expectancy was similar among the 3 strategies (NUC-FFR = 0.8 quality-adjusted days, FFR-STENT = 6 quality-adjusted life days). Compared with the FFR strategy, the NUC strategy was expensive (>800,000 dollars per quality-adjusted life year gained). Both screening strategies were superior to (less cost, better outcomes) the STENT strategy. Sensitivity analysis indicated that the NUC strategy would only become attractive (<50,000 dollars/quality-adjusted life years compared with FFR) if the specificity of nuclear stress imaging was >25% better than FFR. Our results were not altered significantly by changing the other assumptions.In patients with an intermediate coronary lesion and no prior functional study, measuring FFR to guide the decision to perform PCI may lead to significant cost savings compared with performing nuclear stress imaging or with simply stenting lesions in all patients.

    View details for DOI 10.1016/S0002-8703(03)00072-3

    View details for Web of Science ID 000183258300020

    View details for PubMedID 12766748

  • Adjunctive platelet glycoprotein IIb/IIIa receptor inhibition with tirofiban before primary Angioplasty improves angiographic outcomes - Results of the TIrofiban given in the emergency room before primary angioplasty (TIGER-PA) pilot trial CIRCULATION Lee, D. P., Herity, N. A., Hiatt, B. L., Fearon, W. F., Rezaee, M., Carter, A. J., Huston, M., Schreiber, D., DiBattiste, P. M., Yeung, A. C. 2003; 107 (11): 1497-1501

    Abstract

    Previous work has suggested that platelet glycoprotein IIb/IIIa receptor blockade may confer benefit in the treatment of acute myocardial infarction. The TIGER-PA pilot trial was a single-center randomized study to evaluate the safety, feasibility, and utility of early tirofiban administration before planned primary angioplasty in patients presenting with acute myocardial infarction.A total of 100 patients presenting with acute myocardial infarction were randomized to either early administration of tirofiban in the emergency room or later administration in the catheterization laboratory. The primary outcome measures were initial TIMI grade flow, corrected TIMI frame counts, and TIMI grade myocardial perfusion ("blush"). Thirty-day major adverse cardiac events were also assessed. Angiographic outcomes demonstrate a significant improvement in initial TIMI grade flow, corrected TIMI frame counts, and TIMI grade myocardial perfusion when patients are given tirofiban in the emergency room before primary angioplasty. The rate of 30-day major adverse cardiac events suggests that early administration may be beneficial.This pilot study suggests that early administration of tirofiban improves angiographic outcomes and is safe and feasible in patients undergoing primary angioplasty for acute myocardial infarction.

    View details for DOI 10.1161/01.CIR.0000056120.00513.7A

    View details for Web of Science ID 000181764600010

    View details for PubMedID 12654606

  • A successful strategy to improve door-to-balloon times in acute myocardial infarction: a single center experience. Critical pathways in cardiology Hiatt, B. L., Lee, D. P., Yeung, A. C. 2002; 1 (2): 103-106

    View details for PubMedID 18340293

  • Targeting the adventitia with intracoronary beta-radiation: Comparison of two dose prescriptions and the role of centering in coronary arteries INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS Kaluza, G. L., Jenkins, T. P., Mourtada, F. A., Ali, N. M., Lee, D. P., Okura, H., Fitzgerald, P. J., Raizner, A. E. 2002; 52 (1): 184-191

    Abstract

    To compare by intravascular ultrasound (IVUS) the efficacy of delivering the prescribed dose to the adventitia between two commonly used dose prescriptions for intracoronary radiotherapy.In 59 human postangioplasty coronary vessels, one IVUS cross-section (1 mm thick) with the highest plaque burden was used for creating dose-volume histograms with different hypothetical positions of the source.On average, prescription to 1 mm beyond lumen surface resulted in delivery of the prescribed dose (20 Gy +/- 20%) to a higher fraction of adventitial volume than with the prescription to 2 mm from the source, with source placed in vessel center, lumen center, or in the IVUS catheter position. Source placement in the lumen center resulted in a low dose heterogeneity to the adventitia and the least dose heterogeneity to the intima.Prescription to 1 mm beyond lumen surface appeared more effective in delivering the prescribed dose to the adventitia than the American Association of Physicists in Medicine (AAPM) recommended prescription to 2 mm from the source center. Moreover, centering the source in the lumen provides the better balance of effective adventitial targeting and intimal dose homogeneity. Modification of the current AAPM recommendation for dose prescription for intracoronary radiotherapy should be considered.

    View details for Web of Science ID 000173105100023

    View details for PubMedID 11777637

  • Predictors and outcomes of stent thrombosis - An intravascular ultrasound registry EUROPEAN HEART JOURNAL Uren, N. G., Schwarzacher, S. P., Metz, J. A., Lee, D. R., Honda, Y., Yeung, A. C., Fitzgerald, P. J., Yock, P. G. 2002; 23 (2): 124-132

    Abstract

    To investigate whether intravascular ultrasound provides additional information regarding the prediction of stent thrombosis, a retrospective multicentre registry was designed to enrol patients with stent thrombosis following stent deployment under ultrasound guidance.A total of 53 patients were enrolled (mean age 61+/-9 years) with stable angina (43%), unstable angina (36%), and post-infarct angina (21%) who underwent intracoronary stenting. The majority had balloon angioplasty alone prior to stenting (94%) with 6% also undergoing rotational atherectomy. The indication for stenting was elective (53%), suboptimal result (32%) and bailout (15%). There were 1.6+/-0.8 stents/artery with 87% undergoing high-pressure dilatation (> or =14 atmospheres). The minimum stent area was 7.7+/-2.8 mm(2)with a mean stent expansion of 81.5+/-21.9%. Overall, 94% of cases demonstrated one abnormal ultrasound finding (stent under-expansion, malapposition, inflow/outflow disease, dissection, or thrombus). Angiography demonstrated an abnormality in only 32% of cases (chi-square=30.0, P<0.001). Stent thrombosis occurred at 132+/-125 h after deployment. Myocardial infarction occurred in 67% and there was an overall mortality of 15%.On comparison with angiography, the vast majority of stents associated with subsequent thrombosis have at least one abnormal feature by intravascular ultrasound at the time of stent deployment.

    View details for DOI 10.1053/euhj.2001.2707

    View details for Web of Science ID 000173390100009

    View details for PubMedID 11785994

  • Clinical utility of the exercise ECG in patients with diabetes and chest pain CHEST Lee, D. P., Fearon, W. F., Froelicher, V. F. 2001; 119 (5): 1576-1581

    Abstract

    The purpose of this study was to determine the characteristics of exercise treadmill testing in diabetic patients presenting with chest pain.The diagnosis of coronary artery disease (CAD) in diabetic patients is confounded by different manifestations of coronary disease than are seen in the general population. Because of the association of diabetes with accelerated CAD, it is critical to assess the diagnostic utility of the standard exercise test in diabetic patients with chest pain.This study was a retrospective analysis of standard exercise test results in 1,282 male patients without prior myocardial infarction who had undergone coronary angiography and were being evaluated for possible CAD at two Veterans' Administration institutions.In patients with diabetes, 38% had an abnormal exercise test result, and the prevalence of angiographic CAD was 69%; the sensitivity of the exercise test was 47% (95% confidence interval [CI], 41 to 58), and specificity was 81% (95% CI, 68 to 89). In patients without diabetes, 38% had an abnormal exercise test result, and the prevalence of angiographic CAD was 58%; the sensitivity of the exercise test was 52% (95% CI, 48 to 56), and specificity was 80% (95% CI, 76 to 83). The receiver operating characteristic curves were also similar in both diabetic and nondiabetic patients (0.67 and 0.68, respectively).These data demonstrate that the standard exercise test has similar diagnostic characteristics in diabetic as in nondiabetic patients.

    View details for Web of Science ID 000168711400042

    View details for PubMedID 11348969

  • Effect of audit on door-to-inflation times in primary angioplasty/stenting for acute myocardial infarction AMERICAN JOURNAL OF CARDIOLOGY Ward, M. R., Lo, S. T., Herity, N. A., Lee, D. P., Yeung, A. C. 2001; 87 (3): 336-?

    Abstract

    We found that after audit and physician-guided changes in our protocol, the door-to-inflation times for primary angioplasty/stenting were markedly reduced. Because our preaudit mean time was similar to the national average, this may have wide applicability.

    View details for Web of Science ID 000166629100017

    View details for PubMedID 11165972

  • Utility of mechanical rheolysis as an adjunct to rescue angioplasty and platelet inhibition in acute myocardial infarction and cardiogenic shock: A case report CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS Lee, D. P., Lo, S., Herity, N. A., Ward, M., Yeung, A. C. 2001; 52 (2): 220-225

    Abstract

    We describe the value of mechanical rheolysis as an adjunct to rescue angioplasty and platelet glycoprotein IIb/IIIa receptor inhibition in a patient with acute myocardial infarction and cardiogenic shock in whom the severity of the intracoronary thrombus burden precluded restoration of antegrade coronary flow by conventional balloon angioplasty and stenting.

    View details for Web of Science ID 000166723500018

    View details for PubMedID 11170334

  • A 25-year-old with severe coronary artery disease LANCET Ward, M. R., Herity, N. A., Lee, D. P., Yeung, A. C. 2001; 357 (9250): 116-116

    View details for Web of Science ID 000166476200015

    View details for PubMedID 11197400

  • Impact of plaque burden on subsequent intimal proliferation and remodeling of the stented coronary arteries following intracoronary beta-radiation therapy. Cardiovascular radiation medicine Okura, H., Lee, D. P., Yeung, A. C., Oesterle, S. N., Waksman, R., Kaluza, G. L., Ali, N. M., Yock, P. G., Raizner, A. E., Fitzgerald, P. J. 2001; 2 (1): 57

    View details for PubMedID 11068273

  • The influence of plaque orientation (pericardial or myocardial) on coronary arterial remodeling ATHEROSCLEROSIS Ward, M. R., Jeremias, A., Hibi, K., Herity, N. A., Lo, S. T., Filardo, S. D., Lee, D. P., Fitzgerald, P. J., Yeung, A. C. 2001; 154 (1): 179-183

    Abstract

    Many systemic, regional and lesion factors have been identified which may influence arterial remodeling, but little is known about the importance of extravascular resistance to vessel enlargement. As myocardial systolic splinting may significantly affect vessel expansion the effect of plaque orientation on arterial remodeling in eccentric coronary atherosclerotic lesions was examined.Using intravascular ultrasound imaging to obtain cross-sectional vessel area (VA), plaque area (PA) and lumen area (LA), remodeling in eccentric left anterior descending coronary artery lesions was compared which predominantly involved the pericardial or free arc (P, n=25) and the myocardial side (M, n=40) of the vessel wall. Normalized vessel area (NVA, VA(lesion)/VA(reference)) was compared as a continuous and categorical variable (positive>1.05, intermediate 0.95-1.05, negative<0.95) as well as remodeling index (RI, VA(lesion)-VA(reference)/PA(lesion)-PA(reference)).The two groups were well matched for clinical and lesion characteristics known to affect remodeling. Reference segments areas were similar in the two groups; while lesion LA was also similar, in the pericardial group there was significantly greater lesion PA (P 12.78+/-0.72, M 10.26+/-0.50 mm(2), P<0.05) and VA (P 15.71+/-0.90, M 12.82+/-0.57 mm(2), P<0.05) demonstrating enhanced compensatory remodeling. Outward remodeling was significantly greater in P than in M by both NVA (P 1.03+/-0.03, M 0.86+/-0.03, P<0.01) and RI (P 0.02+/-0.07, M -1.10+/-0.32, P<0.01). Positive, intermediate and negative remodeling occurred in nine, nine and seven lesions in P and in four, ten and 26 lesions in M (P<0.01).Remodeling compensates more for plaque growth in eccentric coronary lesions which are surrounded by the pericardium than those surrounded by the myocardium. Extravascular resistance appears to influence arterial remodeling.

    View details for Web of Science ID 000166116000022

    View details for PubMedID 11137098

  • Selective regional myocardial infiltration by the percutaneous coronary venous route: A novel technique for local drug delivery CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS Herity, N. A., Lo, S. T., Oei, F., Lee, D. P., Ward, M. R., Filardo, S. D., Hassan, A., Suzuki, T., Rezaee, M., Carter, A. J., Yock, P. G., Yeung, A. C., Fitzgerald, P. J. 2000; 51 (3): 358-363

    Abstract

    Recent advances in the treatment of heart disease, in particular cardiovascular gene therapy and therapeutic angiogenesis, highlight the need for efficient and practical local delivery methods for the heart. We assessed the feasibility of percutaneous selective coronary venous cannulation and injection as a novel approach to local myocardial drug delivery. In anesthetized swine, the coronary sinus was cannulated percutaneously and a balloon-tipped catheter advanced to the anterior interventricular vein (AIV) or middle cardiac vein (MCV). During balloon occlusion, venous injection of radiographic contrast caused regional infiltration of targeted myocardial regions. Complete AIV occlusion had no impact on LAD flow parameters. Videodensitometric analysis following venous injection showed that radiographic contrast persisted for at least 30 min. Selective regional myocardial infiltration is feasible by this approach, targeting selected myocardial beds, including the apex, anterior wall, septum, and inferoposterior wall. This novel technique has potential application for local myocardial drug or growth factor delivery. Cathet. Cardiovasc. Intervent. 51:358-363, 2000.

    View details for Web of Science ID 000165141100027

    View details for PubMedID 11066126

  • Spatial orientation of atherosclerotic plaque in non-branching coronary artery segments ATHEROSCLEROSIS Jeremias, A., Huegel, H., Lee, D. P., Hassan, A., Wolf, A., Yeung, A. C., Yock, P. G., Fitzgerald, P. J. 2000; 152 (1): 209-215

    Abstract

    It has been postulated that atherosclerotic plaque deposition is spatially related to regions of low shear in non-branching vessel segments. Intravascular ultrasound (IVUS) allows precise spatial orientation of coronary artery plaque formation in humans. The objective of this study was to test the hypothesis that coronary plaques have a higher prevalence on the myocardial side in regions that encounter low surface shear stress. IVUS allows the determination of the inner versus the outer curve of the vessel based on vascular and perivascular landmarks. We studied 30 consecutive patients pre-intervention using IVUS and measured vessel area, lumen area and plaque area (vessel-lumen area) during a motorized pullback at 1 mm intervals. Vessel segments near a side branch (within two times the diameter of the vessel) were excluded from analysis because of flow disturbances. All plaques were classified as concentric or eccentric and all eccentric plaques were further divided with respect to their spatial orientation in the vessel into quadrants: myocardial (inner curve, lower shear stress), epicardial (outer curve, higher shear stress) and lateral (two quadrants intermediate). A total of 613 cross-sections were analyzed in 14 left anterior descending, six left circumflex, and ten right coronary arteries. Plaque distribution was found to be concentric in 321 (52.4%) and eccentric in 292 (47.6%) cross sections. Of all eccentric plaques, 184 cross sections were oriented toward the myocardial side (62.6%) compared to only 54 toward the epicardial side (17.3%) and 54 in the 2 lateral quadrants (19.5%, P<0.001). No difference in plaque area (6.75+/-2.70 vs. 6.76+/-2.60 mm(2)), vessel area (15.28+/-4.73 vs. 15.35+/-4.40 mm(2)), or plaque thickness (1.26+/-0.37 vs. 1.25+/-0.43 mm) was noted between myocardial or epicardial plaques. These results suggest that atherosclerotic plaques develop more frequently on the myocardial side of the vessel wall, which may relate to lower shear stress. However, plaque size is similar on the epicardial and myocardial side.

    View details for Web of Science ID 000089447700025

    View details for PubMedID 10996357

  • Experimental evaluation of a short transitional edge protection balloon for intracoronary stent deployment CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS Carter, A. J., Lee, D. P., Suzuki, T., Bailey, L., Lansky, A., Jones, R., Virmani, R. 2000; 51 (1): 112-119

    Abstract

    The purpose of this study was to determine if balloon injury to the adjacent arterial wall during intracoronary stent deployment influences late in-stent neointimal formation. Stent design and deployment techniques are considered important factors in determining acute and long-term success with intracoronary stenting. Experimental and clinical studies support that the extent of neointimal formation and the probability for restenosis are influenced by the magnitude of arterial trauma induced with stenting. Nineteen 18-mm-long balloon-expandable stainless steel stents (MULTI-LINK Duet) were implanted at a 1:1 stent-to-artery ratio in the coronary arteries of swine with a conventional noncompliant balloon (n = 10) or a novel noncompliant balloon with short tapered shoulders to prevent edge dissection (n = 9). Quantitative coronary angiography and histology were used to evaluate balloon and artery interactions and the chronic vascular responses to the stents. Nineteen stents were implanted in the coronary arteries of seven swines at an inflation pressure of 14 atm using a standard noncompliant (n = 10) or a unique short transitional edge protection (n = 9) balloon. Histologic analysis at 28 days demonstrated balloon-associated barotrauma in 13 of 20 (65%) of adjacent nonstented arterial segments with the conventional balloon and only 3 of 18 (17%) of the adjacent nonstented arterial segments with the short transition edge protection balloon (P = 0.022). In-stent neointimal area and % stenosis correlated with the severity of peristent arterial injury (r = 0.43, P = 0.01). In-stent vessel injury scores were similar for stents with peristent injury (1.0+/-0.3) versus stents without peristent injury (1.0+/-0.03, P = 0.73). In-stent neointimal area and % stenosis were greater for stents with peristent injury (2.36+/-0.74 mm(2), 32%+/-9%) as compared to stents without peristent injury (1.39+/-0.70 mm(2), 20%+/-10%, P = 0.01). Arterial wall injury adjacent to a stent after high-pressure deployment contributes to late in-stent neointimal hyperplasia in this model. These experimental data suggest that further study is warranted to refine stent implantation techniques and that modifications of balloon shape or material may be useful to optimize stent deployment and reduce arterial trauma.

    View details for Web of Science ID 000089106300026

    View details for PubMedID 10973033

  • Patterns of aspirin use before hospitalization for acute myocardial infarction AMERICAN JOURNAL OF CARDIOLOGY Lorenz, D. P., Lee, D. P., Alderman, E. 2000; 86 (2): 214-216

    View details for Web of Science ID 000088125300016

    View details for PubMedID 10913485

  • The effect of resting ST segment depression on the diagnostic characteristics of the exercise treadmill test JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Fearon, W. F., Lee, D. P., Froelicher, V. F. 2000; 35 (5): 1206-1211

    Abstract

    The aim of this study is to demonstrate the effect of resting ST segment depression on the diagnostic characteristics of the exercise treadmill test.Previous studies evaluating the effect of resting ST segment depression on the diagnostic characteristics of exercise treadmill test have been conducted on relatively small patient groups and based only on visual electrocardiogram (ECG) analysis.A retrospective analysis of data collected prospectively was performed on consecutive patients referred for evaluation of chest pain. One thousand two hundred eighty-two patients without a prior myocardial infarction underwent standard exercise treadmill tests followed by coronary angiography, with coronary artery disease defined as a 50% narrowing in at least one major epicardial coronary artery. Sensitivity, specificity, predictive accuracy and area under the curve of the receiver operating characteristic (ROC) plots were calculated for patients with and without resting ST segment depression as determined by visual or computerized analysis of the baseline ECG.Sensitivity of the exercise treadmill test increased in 206 patients with resting ST segment depression determined by visual ECG analysis compared with patients without resting ST segment depression (77 +/- 7% vs. 45 +/- 4%) and specificity decreased (48 +/- 12% vs. 84 +/- 3%). With computerized analysis, sensitivity of the treadmill test increased in 349 patients with resting ST segment depression compared with patients without resting ST segment depression (71 +/- 6% vs. 42 +/- 4%) and specificity decreased (52 +/- 9% vs. 87 +/- 3%) (p < 0.0001 for all comparisons). There was no significant difference in the area under the curve of the ROC plots (0.66-0.69) or the predictive accuracy (62-68%) between the four subgroups.The diagnostic accuracy and high sensitivity of the exercise treadmill test in a large cohort of patients with resting ST segment depression and no prior myocardial infarction support the initial use of the test for diagnosis of coronary artery disease. The classification of resting ST segment depression by method of analysis (visual vs. computerized) did not affect the results.

    View details for Web of Science ID 000086265900015

    View details for PubMedID 10758962

  • Acute myocardial infarction and vascular remodeling AMERICAN JOURNAL OF CARDIOLOGY Filardo, S. D., Schwarzacher, S. P., Lo, S. T., Herity, N. A., Lee, D. P., Huegel, H., Mullen, W. L., Fitzgerald, P. J., Ward, M. R., Yeung, A. C. 2000; 85 (6): 760-?

    Abstract

    We used intravascular ultrasound to show that outward remodeling predominates in lesions responsible for acute myocardial infarction, whereas negative remodeling is far more prevalent in lesions responsible for chronic stable angina. The total cholesterol:high-density lipoprotein ratio was also strongly correlated with outward remodeling.

    View details for Web of Science ID 000085838000018

    View details for PubMedID 12000055

  • Clinical applications of brachytherapy for the prevention of restenosis VASCULAR MEDICINE Lee, D. P., Lo, S., Forster, K., Yeung, A. C., Oesterle, S. N. 1999; 4 (4): 257-268

    Abstract

    Restenosis remains the bane of percutaneous coronary intervention. Local delivery of radiation, brachytherapy, is a promising therapy for the prevention of restenosis. Animal studies have suggested that brachytherapy may be an effective treatment for preventing restenosis. The type of radiation as well as the doses and delivery systems are currently under study; several clinical trials are underway. This paper reviews the biological basis, including animal studies, of intracoronary brachytherapy as well as the current data from clinical trials.

    View details for Web of Science ID 000084256600009

    View details for PubMedID 10613631

  • Intracoronary radiation with a P-32 source wire HERZ Lee, D. P., Lo, S., Forster, K. M., Tate, D. J., Raizner, A., Oesterle, S. N. 1998; 23 (6): 362-365

    Abstract

    The Proliferation REduction with Vascular ENergy Trial (PREVENT) is a prospective randomized study of the safety and efficacy of intracoronary brachytherapy to reduce restenosis. A beta-emitter, 32P, is embedded on a wire tip and delivered to the target site through a centering catheter immediately following a coronary intervention. The radiation doses are 16, 20, and 24 Gy measured at 1 mm within the vessel wall. Follow-up includes an angiogram and IVUS at 6 months. Phase I of this trial has been completed with results expected in early 1999.

    View details for Web of Science ID 000076260300005

    View details for PubMedID 9816522

Conference Proceedings


  • Safety and Efficacy of Drug Eluting Stents for Treatment of Cardiac Allograft Vasculopathy: A Prospective Clinical and Angiographic Study Ng, M. K., Tremmel, J., Ikeno, F., Lee, D. P., Yeung, A. C., Fearon, W. F. EXCERPTA MEDICA INC-ELSEVIER SCIENCE INC. 2009: 138D-138D
  • Index of microcirculatory resistance: A novel measure for predicting myocardial damage in patients with acute myocardial infarction Shah, M., Tremmel, J., Brinton, T., Wilson, A., Schnittger, I., Lee, D. P., Yeung, A. C., Fearon, W. F. LIPPINCOTT WILLIAMS & WILKINS. 2006: 586-587
  • Rapamycin therapy improves coronary physiology after cardiac transplantation Sinha, S. S., Lee, D. P., Pham, M. X., Vagelos, R. H., Hunt, S. A., Valentine, H. A., Yeung, A. C., Fearon, W. F. ELSEVIER SCIENCE INC. 2006: 51A-51A
  • Index of microcirculatory resistance: A novel measure for predicting myocardial damage in patients with acute myocardial infarction Shah, M. G., Tremmel, J., Brinton, T., Wilson, A., Schnittger, I., Lee, D. P., Yeung, A. C., Fearon, W. F. ELSEVIER SCIENCE INC. 2006: 182A-182A
  • Women remain at higher risk for retroperitoneal hematoma after percutaneous coronary intervention in the era of glycoprotein IIb/IIIa inhibitors and vascular closure devices Farouque, H. M., Tremmel, J. A., Aggarwal, M., Shabari, F. R., Fearon, W. F., Rezaee, M., Yeung, A. C., Lee, D. P. ELSEVIER SCIENCE INC. 2004: 63A-63A
  • Physiologic interrogation of transplant arterioparthy: Final results Fearon, W. F., Nakamura, M., Lee, D. P., Rezaee, M., Vagelos, R. H., Hunt, S. A., Fitzgerald, P. J., Yock, P. G., Yeung, A. C. ELSEVIER SCIENCE INC. 2003: 29A-29A
  • Physiologic interrogation of transplant arteriopathy Fearon, W. F., Nakamura, M., Lee, D. P., Rezaee, M., Vagelos, R. H., Hunt, S. A., Yock, P. G., Yeung, A. C. LIPPINCOTT WILLIAMS & WILKINS. 2002: 591-591
  • Safety and efficacy of high pressure retrograde cardiac venous injection. Implications for regional myocardial delivery Herity, N. A., Fearon, W., Hiatt, B. L., Rezaee, M., Suzuki, T., Lee, D. P., Yeung, A. C., Carter, A. J., Fitzgerald, P. J., Yock, P. G. ELSEVIER SCIENCE INC. 2001: 6A-6A
  • Intracardiac venous system as a novel conduit for local drug delivery Rezaee, M., Lo, S. T., Bailey, L., Suzuki, T., Lee, D. P., Yock, P. G., Fitzgerald, P. J., Yeung, A. C., Stertzer, S., Carter, A. ELSEVIER SCIENCE INC. 2000: 6A-6A

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