Patrick M McCarthy

Baylor Hamilton Heart and Vascular Hospital, Dallas, Texas, United States

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Publications (545)3253.31 Total impact

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    ABSTRACT: Background: Current guidelines recommend at least 24-hour Holter monitoring at 6-month intervals to evaluate the recurrence of atrial fibrillation (AF) after surgical ablation. In this prospective multicenter study, conventional intermittent methods of AF monitoring were compared with continuous monitoring using an implantable loop recorder (ILR). Methods: From August 2011 to January 2014, 47 patients receiving surgical treatment for AF at 2 institutions had an ILR placed at the time of operation. Each atrial tachyarrhythmia (ATA) of 2 minutes or more was saved. Patients transmitted ILR recordings bimonthly or after any symptomatic event. Up to 27 minutes of data was stored before files were overwritten. Patients also underwent electrocardiography (ECG) and 24-hour Holter monitoring at 3, 6, and 12 months. ILR compliance was defined as any transmission between 0 and 3 months, 3 and 6 months, or 6 and 12 months. Freedom from ATAs was calculated and compared. Results: ILR compliance at 12 months was 93% compared with ECG and Holter monitoring compliance of 85% and 76%, respectively. ILR devices reported a total of 20,878 ATAs. Of these, 11% of episodes were available for review and 46% were confirmed as AF. Freedom from ATAs was no different between continuous and intermittent monitoring at 1 year. Symptomatic events accounted for 187 episodes; however, only 10% were confirmed as AF. Conclusions: ILR was equivalent at detecting ATAs when compared with Holter monitoring or ECG. However, the high rate of false-positive readings and the limited number of events available for review present barriers to broad implementation of this form of monitoring. Very few symptomatic events were AF on review.
    Full-text · Article · Oct 2015 · The Annals of thoracic surgery
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    ABSTRACT: Objective: The aim of this study was to systematically investigate a newly developed semiautomated workflow for the analysis of aortic 4-dimensional flow MRI and its ability to detect hemodynamic differences in patients with congenitally altered aortic valve (bicuspid or quadricuspid valves) compared with tricuspid aortic valves. Methods: Four-dimensional flow MRI data were acquired in 20 patients with aortic dilatation (9 tricuspid aortic valves, 11 congenitally altered aortic valves). A semiautomated workflow was evaluated regarding interobserver variability, accuracy of net flow, regurgitant fraction and peak systolic velocity, and the ability to detect differences between cohorts. Results were compared with manual segmentation of vessel contours. Results: Despite the significantly reduced analysis time, a good interobserver agreement was found for net flow and peak systolic velocity, and a moderate agreement was found for regurgitation. Significant differences in peak velocities in the descending aorta (P = 0.014) could be detected. Conclusions: Four-dimensional flow MRI-based semiautomated analysis of aortic hemodynamics can be performed with good reproducibility and accuracy.
    No preview · Article · Oct 2015 · Journal of computer assisted tomography
  • W.D. Kent · S.C. Malaisrie · A. Andrei · P.W. Fedak · J. Kruse · Z. Li · P.M. McCarthy

    No preview · Article · Oct 2015 · The Canadian journal of cardiology

  • No preview · Article · Oct 2015 · The Canadian journal of cardiology
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    ABSTRACT: Background: Gender disparities have been established in patients who have atrial fibrillation (AF), and in their outcomes after medical treatment for AF. This study evaluated differences in outcome by gender in patients who underwent surgical treatment for AF. Methods: From April 2004 to December 2012, a total of 936 patients had surgical treatment for AF. Outcomes were analyzed by gender using propensity score-matching methods. Results: Of the 936 subjects, 571 (61%) were men; women were older (aged 68.6 ± 11.3 vs 66.9 ± 11.9 years; P = .033), had more heart failure (44% vs 37%; P = .024), more mitral valve surgery (72% vs 50%; P < .001) and more tricuspid valve surgery (41% vs 18%; P < .001). Men underwent more coronary artery bypass surgery (37% vs 19%; P < .001) and aortic valve surgery (38% vs 31%; P = .029). Women had higher late stroke rate per 10 person-years (0.15 vs 0.07; P = .035), fewer catheter ablations (6.0% vs 9.8%; P = .017), and a trend toward fewer cardioversions for recurrent AF (15.7% vs 19.2%; P = .20). After propensity-score matching, late stroke rates per 10 person-years trended higher in women (0.12 vs 0.04; P = .13). No significant gender differences were found in overall survival (5-year survival: 78.8% in men, and 81.0% in women; P = .40) or freedom from AF without antiarrhythmic drugs at last follow-up (71.8% in men vs 73.6% in women, P = .59). Conclusions: Women sought surgery treatment at older ages and with more heart failure. No gender-based differences were found in stroke, overall survival, or procedure success, after propensity-score matching.
    No preview · Article · Sep 2015 · Journal of Thoracic and Cardiovascular Surgery
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    ABSTRACT: Background: The Cox Maze-IV procedure (CMP-IV) has replaced the Cox Maze-III procedure as the most common approach for the surgical treatment of atrial fibrillation (AF). The Food and Drug Administration-regulated AtriCure Bipolar Radiofrequency Ablation of Permanent Atrial Fibrillation (ABLATE) trial sought to demonstrate the safety and efficacy of the CMP-IV performed with the Synergy ablation system (AtriCure, Inc, Cincinnati, OH). Methods: Fifty-five patients (aged 70.5 ± 9.3 years), 92.7% of whom had nonparoxysmal AF, underwent CMP-IV to terminate AF during a concomitant cardiac surgical procedure. Lesions were created using the AtriCure Synergy bipolar radiofrequency ablation system. All patients were seen for follow-up visits after 30 days, 3 months, and 6 months, with 24-hour Holter monitoring at 6 months. Late evaluation was performed by 48-hour Holter monitoring at an average of 21 months. Results: The primary efficacy endpoint, absence of AF (30 seconds or less) at 6-month follow-up off antiarrhythmic medications (Heart Rhythm Society definition), indicated 76% (38 of 50) were AF free (95% confidence interval: 62.6% to 85.7%). The primary safety endpoint, the rate of major adverse events within 30 days, was 9.1% (5 of 55; 95% confidence interval: 3.9% to 19.6%), with 3.6% mortality (2 of 55). Secondary efficacy endpoints included being AF free with antiarrhythmic drugs (6 months, 84%; 21 months, 75%), successful pulmonary vein isolation (100%), and AF burden at 6 and 21 months. The results, together with those for the secondary safety endpoint (6-month major adverse events), demonstrated that the Synergy system performs comparably to the cut-and-sew Cox Maze-III procedure. Conclusions: The CMP-IV using the AtriCure Synergy system was safe and effective for cardiac surgical patients who had persistent and longstanding persistent AF.
    Full-text · Article · Sep 2015 · The Annals of thoracic surgery
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    ABSTRACT: BACKGROUND Suspected genetic causes for extracellular matrix (ECM) dysregulation in the ascending aorta in patients with bicuspid aortic valves (BAV) have influenced strategies and thresholds for surgical resection of BAV aortopathy. Using 4-dimensional (4D) flow cardiac magnetic resonance imaging (CMR), we have documented increased regional wall shear stress (WSS) in the ascending aorta of BAV patients. OBJECTIVES This study assessed the relationship between WSS and regional aortic tissue remodeling in BAV patients to determine the influence of regional WSS on the expression of ECM dysregulation. METHODS BAV patients (n 1⁄4 20) undergoing ascending aortic resection underwent pre-operative 4D flow CMR to regionally map WSS. Paired aortic wall samples (i.e., within-patient samples obtained from regions of elevated and normal WSS) were collected and compared for medial elastin degeneration by histology and ECM regulation by protein expression. RESULTS Regions of increased WSS showed greater medial elastin degradation compared to adjacent areas with normal WSS: decreased total elastin (p 1⁄4 0.01) with thinner fibers (p 1⁄4 0.00007) that were farther apart (p 1⁄4 0.001). Multiplex protein analyses of ECM regulatory molecules revealed an increase in transforming growth factor b-1 (p 1⁄4 0.04), matrix metalloproteinase (MMP)-1 (p 1⁄4 0.03), MMP-2 (p 1⁄4 0.06), MMP-3 (p 1⁄4 0.02), and tissue inhibitor of metalloproteinase-1 (p 1⁄4 0.04) in elevated WSS regions, indicating ECM dysregulation in regions of high WSS. CONCLUSIONS Regions of increased WSS correspond with ECM dysregulation and elastic fiber degeneration in the ascending aorta of BAV patients, implicating valve-related hemodynamics as a contributing factor in the development of aortopathy. Further study to validate the use of 4D flow CMR as a noninvasive biomarker of disease progression and its ability to individualize resection strategies is warranted. (J Am Coll Cardiol 2015;66:892–900) © 2015 by the American College of Cardiology Foundation.
    Full-text · Article · Aug 2015 · Journal of the American College of Cardiology
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    ABSTRACT: Suspected genetic causes for extracellular matrix (ECM) dysregulation in the ascending aorta in patients with bicuspid aortic valves (BAV) have influenced strategies and thresholds for surgical resection of BAV aortopathy. Using 4-dimensional (4D) flow cardiac magnetic resonance imaging (CMR), we have documented increased regional wall shear stress (WSS) in the ascending aorta of BAV patients. This study assessed the relationship between WSS and regional aortic tissue remodeling in BAV patients to determine the influence of regional WSS on the expression of ECM dysregulation. BAV patients (n = 20) undergoing ascending aortic resection underwent pre-operative 4D flow CMR to regionally map WSS. Paired aortic wall samples (i.e., within-patient samples obtained from regions of elevated and normal WSS) were collected and compared for medial elastin degeneration by histology and ECM regulation by protein expression. Regions of increased WSS showed greater medial elastin degradation compared to adjacent areas with normal WSS: decreased total elastin (p = 0.01) with thinner fibers (p = 0.00007) that were farther apart (p = 0.001). Multiplex protein analyses of ECM regulatory molecules revealed an increase in transforming growth factor β-1 (p = 0.04), matrix metalloproteinase (MMP)-1 (p = 0.03), MMP-2 (p = 0.06), MMP-3 (p = 0.02), and tissue inhibitor of metalloproteinase-1 (p = 0.04) in elevated WSS regions, indicating ECM dysregulation in regions of high WSS. Regions of increased WSS correspond with ECM dysregulation and elastic fiber degeneration in the ascending aorta of BAV patients, implicating valve-related hemodynamics as a contributing factor in the development of aortopathy. Further study to validate the use of 4D flow CMR as a noninvasive biomarker of disease progression and its ability to individualize resection strategies is warranted. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
    No preview · Article · Aug 2015 · Journal of the American College of Cardiology
  • Patrick M McCarthy

    No preview · Article · Aug 2015 · The Journal of thoracic and cardiovascular surgery
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    ABSTRACT: Accurate risk assessment in patients presenting for aortic valve replacement (AVR) after prior coronary artery bypass grafting (CABG) is essential for appropriate selection of surgical versus percutaneous therapy. We included 6,534 patients in The Society for Thoracic Surgeons (STS) Adult Cardiac Surgery Database (October 2009 through December 2013) who underwent elective, isolated reoperative AVR for aortic stenosis after prior CABG. Case-specific PROM was calculated and observed-to-expected ratios were inspected across the spectrum of risk. A cohort-specific recalibration equation was derived using logistic regression: = expit(-0.6453+0.6147*logit(PROM) -0.0709*logit(PROM)(ˆ)2), where PROM is the predicted risk of mortality. The proportion of patients reclassified as low (PROM < 4%), intermediate (4% to < 8%), high (8% to < 12%), and very high risk (≥12%) was calculated using the recalibration equation. The performance of the cohort-specific recalibration equation was then compared with the generic recalibration for quarterly STS reports. The STS online risk calculator overestimates risk for low, intermediate, and high risk categories. Using the recalibrated risk equation, a substantial proportion of patients were reclassified as the following: 25.5% from intermediate to low risk; 39.7% from high to intermediate risk; and 41.5% from very high to high risk. Comparison of the cohort-specific recalibration equation to the generic quarterly STS recalibration demonstrated very similar results. In patients presenting for AVR after prior CABG, the STS online risk calculator overestimates risk for all but the highest risk patients. Using a cohort-specific recalibration equation, a substantial proportion of patients would be downgraded to lower risk categories. The cohort-specific recalibration correlates well with the existing generic quarterly STS recalibration. The findings of this study support recommendations for periodic recalibration of the online risk calculator in order to facilitate clinical decision making in real time. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
    Full-text · Article · Jul 2015 · The Annals of thoracic surgery
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    ABSTRACT: The purpose of this study is to compare aortic hemodynamics and blood flow patterns using in-vivo four-dimensional (4D) flow magnetic resonance imaging (MRI) in patients after valve-sparing aortic root replacement (VSARR) and aortic root replacement with bioprosthetic valves (BIO-ARR). In-vivo 4D flow MRI was performed in 11 patients after VSARR (47 ± 18 years, 6 bicuspid aortic valves, 5 trileaflet aortic valves), 16 patients after BIO-ARR (52 ± 14 years), and 10 healthy controls (47 ± 16 years). Analysis included three-dimensional blood flow visualization and grading of helix flow in the ascending aorta (AAo) and arch. Peak systolic velocity was quantified in 9 analysis planes in the AAo, aortic arch, and descending aorta. Flow profile uniformity was evaluated in the aortic root and ascending aorta. Peak systolic velocity (2.0 to 2.5m/second) in the aortic root and AAo in both VSARR and BIO-ARR were elevated compared with controls (1.1 to 1.3m/second, p < 0.005). Flow asymmetry in BIO-ARR was increased compared with VSARR, evidenced by more AAo outflow jets (9 of 16 BIO-ARR, 0 of 11 in VSARR). The BIO-ARR exhibited significantly (p < 0.001) increased helix flow in the AAo as a measure of increased flow derangement. Finally, peak systolic velocities were elevated at the aortic root for BIO-ARR (2.5 vs 2.0m/second, p < 0.05) but lower in the distal AAo when compared with VSARR. The VSARR results in improved hemodynamic outcomes when compared with BIO-ARR, as indicated by reduced peak velocities in the aortic root and less helix flow in the AAo by 4D flow MRI. Longitudinal research assessing the clinical impact of these differences in hemodynamic outcomes is warranted. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
    No preview · Article · Jul 2015 · The Annals of thoracic surgery
  • Patrick M McCarthy

    No preview · Article · Jul 2015 · The Journal of thoracic and cardiovascular surgery
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    Full-text · Article · Jun 2015 · Journal of the American College of Cardiology
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    ABSTRACT: Objectives: The study objectives were to (1) compare the safety of high-risk surgical aortic valve replacement in the Placement of Aortic Transcatheter Valves (PARTNER) I trial with Society of Thoracic Surgeons national benchmarks; (2) reference intermediate-term survival to that of the US population; and (3) identify subsets of patients for whom aortic valve replacement may be futile, with no survival benefit compared with therapy without aortic valve replacement. Methods: From May 2007 to October 2009, 699 patients with high surgical risk, aged 84 ± 6.3 years, were randomized in PARTNER-IA; 313 patients underwent surgical aortic valve replacement. Median follow-up was 2.8 years. Survival for therapy without aortic valve replacement used 181 PARTNER-IB patients. Results: Operative mortality was 10.5% (expected 9.3%), stroke 2.6% (expected 3.5%), renal failure 5.8% (expected 12%), sternal wound infection 0.64% (expected 0.33%), and prolonged length of stay 26% (expected 18%). However, calibration of observed events in this relatively small sample was poor. Survival at 1, 2, 3, and 4 years was 75%, 68%, 57%, and 44%, respectively, lower than 90%, 81%, 73%, and 65%, respectively, in the US population, but higher than 53%, 32%, 21%, and 14%, respectively, in patients without aortic valve replacement. Risk factors for death included smaller body mass index, lower albumin, history of cancer, and prosthesis-patient mismatch. Within this high-risk aortic valve replacement group, only the 8% of patients with the poorest risk profiles had estimated 1-year survival less than that of similar patients treated without aortic valve replacement. Conclusions: PARTNER selection criteria for surgical aortic valve replacement, with a few caveats, may be more appropriate, realistic indications for surgery than those of the past, reflecting contemporary surgical management of severe aortic stenosis in high-risk patients at experienced sites.
    No preview · Article · Jun 2015 · The Journal of thoracic and cardiovascular surgery
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    ABSTRACT: Paravalvular regurgitation is a known complication after transcatheter and sutureless aortic valve replacement. Paravalvular regurgitation also may develop in patients undergoing percutaneous mitral valve replacement. There are few studies on contemporary surgical valve replacement for comparison. We sought to determine the contemporary occurrence of paravalvular regurgitation after conventional surgical valve replacement. We performed a single-center retrospective database review involving 1774 patients who underwent valve replacement surgery from April 2004 to December 2012: aortic in 1244, mitral in 386, and combined aortic and mitral in 144. Follow-up echocardiography was performed in 73% of patients. Patients with endocarditis were analyzed separately from noninfectious paravalvular leaks. Statistical comparisons were performed to determine differences in paravalvular regurgitation incidence and survival. During follow-up, 1+ or greater (mild or more) paravalvular regurgitation occurred in 2.2% of aortic cases and 2.9% of mitral cases. There was 2+ or greater (moderate or more) paravalvular regurgitation in 0.9% of aortic and 2.2% of mitral cases (P = .10). After excluding endocarditis, late noninfectious regurgitation 2+ or greater was detected in 0.5% of aortic and 0.4% of mitral cases (P = .93); there were no reoperations or percutaneous closures for noninfectious paravalvular regurgitation. In an academic medical center, the overall rate of paravalvular regurgitation is low, and late clinically significant noninfectious paravalvular regurgitation is rare. The benchmark for paravalvular regurgitation after conventional valve replacement is high and should be considered when evaluating patients for transcatheter or sutureless valve replacement. Copyright © 2015 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.
    Full-text · Article · Jun 2015 · The Journal of thoracic and cardiovascular surgery
  • Patrick M McCarthy
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    ABSTRACT: Indentations in the posterior leaflet of the mitral valve are part of the normal anatomy and are the landmarks that surgeons use to distinguish the typical three scallops: P1, P2 and P3. While the typical finding of three scallops occurs in about 90% of patients, there may be more subtle indentations and some have referred to four or more scallops.1 These are just expected biological variation in the complex structure of the mitral valve. Carpentier has noted that these posterior leaflet indentations ‘are normal anatomical structures that allow the leaflet to fully open during diastole’.2 The chords that supply the indentations are typically normal length and have been referred to as ‘cleft chordae’ at least since the 1960s.1 They rarely prolapse or rupture like the ‘marginal’ (primary) chords that supply the free edge of the tip of the scallops.2 The height of the three posterior leaflet scallops varies (table 1) and normally P2 is the tallest and P1 the shortest. In patients with degenerative mitral regurgitation (DMR) (Carpentier type II prolapse), these segments are elongated (table 1), but these lengths are quite variable.3 P2 averaged 19 mm in a recent study and the adjacent P1 scallop was elongated, but still significantly shorter (11 mm).3 View this table: In this window In a new window
    No preview · Article · May 2015 · Heart (British Cardiac Society)
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    ABSTRACT: Gender disparities in short- and long-term outcomes have been documented in cardiac and valvular heart surgery. However, there is a paucity of data regarding these differences in the bicuspid aortic valve (BAV) population. The aim of this study was to examine gender-specific differences in short- and long-term outcomes after surgical aortic valve (AV) replacement in patients with BAV. A retrospective analysis was performed in 628 consecutive patients with BAV who underwent AV surgery from April 2004 to December 2013. To reduce bias when comparing outcomes by gender, propensity score matching obtained on the basis of potential confounders was used. Women with BAV who underwent AV surgery presented with more advanced age (mean 60.7 ± 13.8 vs 56.3 ± 13.6 years, p <0.001) and less aortic regurgitation (29% vs 44%, p <0.001) and had a higher risk for in-hospital mortality (mean Ambler score 3.4 ± 4.4 vs 2.5 ± 4.0, p = 0.015). After propensity score matching, women received more blood products postoperatively (48% vs 34%, p = 0.028) and had more prolonged postoperative lengths of stay (median 5 days [interquartile range 5 to 7] vs 5 days [interquartile range 4 to 6], p = 0.027). Operative, discharge, and 30-day mortality and overall survival were not significantly different. In conclusion, women with BAV who underwent AV surgery were older, presented with less aortic regurgitation, and had increased co-morbidities, lending higher operative risk. Although women received more blood products and had significantly longer lengths of stay, short- and long-term outcomes were similar. Copyright © 2015 Elsevier Inc. All rights reserved.
    Full-text · Article · Apr 2015 · The American journal of cardiology
  • Patrick M McCarthy

    No preview · Article · Apr 2015 · Journal of the American College of Cardiology
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    ABSTRACT: Cardiac papillary fibroelastoma is a rare, benign tumor, arising predominantly from cardiac valves. This tumor can cause a variety of symptoms due to thromboembolism. We describe our single-center surgical experience with papillary fibroelastoma of the aortic valve. From April 2004 through June 2013, 6,530 patients underwent cardiac surgery. Of those, 6,098 patients were included in the final analysis. Twenty-one patients (0.34%) underwent surgical resection of 30 papillary fibroelastomas of the aortic valve. Most patients (67%) were incidentally diagnosed to have cardiac papillary fibroelastoma. The usual symptom was cerebral infarction (in 5 of 7 symptomatic patients). A rare presentation of papillary fibroelastoma in one patient was cardiac arrest caused by left main coronary artery ostial obstruction. Tumor size was not related to patient age (Pearson correlation coefficient, 0.34; P=0.13). Neither the number of tumors (1.43 ± 0.72 vs 1.43 ± 0.62) nor tumor size (8.14 ± 2.42 vs 8.07 ± 3.31 mm) was significantly different between symptomatic and asymptomatic patients. All lesions were resected by means of the simple shave technique. There were no operative or 30-day deaths. Follow-up echocardiograms showed no tumor recurrence (mean follow-up duration, 17 ± 14 mo). We identified no significant relationship among tumor size, number of tumors, symptoms, or patient age. Because simple shave excision of the tumor can be safely achieved without evidence of tumor recurrence, we conclude that surgical resection can be reasonable in asymptomatic patients.
    No preview · Article · Apr 2015 · Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital

  • No preview · Article · Apr 2015

Publication Stats

21k Citations
3,253.31 Total Impact Points

Institutions

  • 2015
    • Baylor Hamilton Heart and Vascular Hospital
      Dallas, Texas, United States
  • 2005-2015
    • Northwestern Memorial Hospital
      • • Department of Surgery
      • • Bluhm Cardiovascular Institute
      Chicago, Illinois, United States
    • Northwestern University
      • • Division of Thoracic Surgery
      • • Feinberg School of Medicine
      • • Division of Cardiac Surgery
      • • Department of Surgery
      • • Bluhm Cardiovascular Institute
      • • Division of Hospital Medicine
      Evanston, Illinois, United States
    • University of Illinois at Chicago
      Chicago, Illinois, United States
    • Medical University of South Carolina
      Charleston, South Carolina, United States
    • Rice University
      • Department of Bioengineering
      Houston, TX, United States
  • 1993-2015
    • The Ohio State University
      • • College of Pharmacy
      • • Department of Biomedical Engineering
      Columbus, Ohio, United States
  • 2012
    • Johns Hopkins Medicine
      Baltimore, Maryland, United States
  • 1998-2007
    • Cleveland Clinic Laboratories
      Cleveland, Ohio, United States
  • 2001-2006
    • Lerner Research Institute
      Cleveland, Ohio, United States
    • University of California, Los Angeles
      • Department of Psychology
      Los Angeles, California, United States
  • 1993-2004
    • Cleveland Clinic
      • • Department of Cardiology
      • • Transplant Center
      Cleveland, Ohio, United States
  • 2003
    • University of Florida Health Science Center-Jacksonville
      Jacksonville, Florida, United States
    • Stanford University
      • Division of Cardiovascular Medicine
      Palo Alto, California, United States
  • 2002
    • Cleveland State University
      • Department of Biological, Geological, and Environmental Sciences
      Cleveland, Ohio, United States
  • 2001-2002
    • Università degli Studi dell'Aquila
      • Department of Internal Medicine and Public Health
      Aquila, Abruzzo, Italy
  • 2000
    • Children's Heart Center
      Las Vegas, Nevada, United States
  • 1997
    • University of Ottawa
      Ottawa, Ontario, Canada
  • 1995
    • Case Western Reserve University
      • Department of Macromolecular Science and Engineering
      Cleveland, OH, United States