Gene Chang
University of Pennsylvania
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Gene Chang.
The New England Journal of Medicine | 2000
Howard C. Herrmann; Gene Chang; Bruce D. Klugherz; Paul Mahoney
BACKGROUND The cardiovascular effects of sildenafil are important because of the frequent presence of underlying cardiac disease in men with erectile dysfunction and reports indicating serious cardiac events temporally associated with the use of this drug. METHODS We assessed the systemic, pulmonary, and coronary hemodynamic effects of oral sildenafil (100 mg) in 14 men (mean [+/-SD] age, 61+/-11 years) with severe stenosis of at least one coronary artery (stenosis of >70 percent of the vessel diameter) who were scheduled to undergo percutaneous coronary revascularization. Blood-flow velocity and flow reserve were assessed with a Doppler guidewire in 25 coronary arteries, including 13 severely diseased arteries (mean stenosis, 78+/-7 percent) and 12 arteries without stenosis, used as a reference; maximal hyperemia was induced (to assess flow reserve) with the intracoronary administration of adenosine both before and after sildenafil. RESULTS Oral sildenafil produced only small decreases (<10 percent) in systemic arterial and pulmonary arterial pressures, and it had no effect on pulmonary-capillary wedge pressure, right atrial pressure, heart rate, or cardiac output. There were no significant changes in average peak coronary flow velocity, coronary-artery diameter, volumetric coronary blood flow, or coronary vascular resistance. Coronary flow reserve at base line was lower in the stenosed arteries (1.26+/-0.26) than in the reference arteries (2.19+/-0.44) and increased about 13 percent in both groups of arteries combined after the administration of sildenafil (from 1.70+/-0.59 to 1.92+/-0.72, P=0.003). The ratio of coronary flow reserve in coronary arteries with stenosis to that in the reference arteries (0.57+/-0.14) was not affected by sildenafil. CONCLUSIONS No adverse cardiovascular effects of oral sildenafil were detected in men with severe coronary artery disease.
Catheterization and Cardiovascular Interventions | 2005
Howard C. Herrmann; Frank E. Silvestry; Ruchira Glaser; Vincent See; Scott E. Kasner; Danielle Bradbury; Gene Chang; John W. Hirshfeld; Phillip A. Horwitz; Michael H. Kelly
Closure of interatrial septal defects with percutaneous devices is increasingly common. However, the indications for closure and techniques for device implantation are diverse. We reviewed our first 100 consecutive implants to assess and compare the indications, results, complications, and evolution of techniques for percutaneous patent foramen ovale (PFO) and atrial septal defect (ASD) closure. The mean age of patients was 52 years and 70% were female. Paradoxical embolism was the predominant indication (94%) for PFO closure and significant left‐to‐right shunt was the most frequent indication (89%) for ASD closure. Implantation success was 94% with major complications in 3 patients (2.8%). Transesophageal echocardiography was utilized in the initial 27 procedures and then replaced by intracardiac echocardiography in subsequent ones, with an associated reduction in procedure and physician time. During 6 months of follow‐up, 3 patients were readmitted for atrial arrhythmias (2 patients) and an MRI‐negative neurologic event (1 patient). Echocardiography at 6 months in 83% of the PFO patients revealed moderate and severe positive contrast studies for right‐to‐left shunting in one third of patients, with differences between devices and insertion techniques. This single‐center experience with percutaneous device closure of PFO and ASD in adults demonstrates excellent results with few complications. Catheter Cardiovasc Interv 2005;64:197–203.
American Journal of Cardiology | 2003
Vincent See; David DeNofrio; Lee R. Goldberg; Gene Chang; Daniel M. Kolansky; Faith Pickering; Andrew Kao; Evan Loh; Robert L. Wilensky
Following cardiac transplantation, accelerated coronary disease limits long-term survival. Because statins may reduce the progression of the disease in part by their anti-inflammatory effects, this study was designed to assess if atorvastatin prevented neointimal hyperplasia and endothelial dysfunction independently of baseline cholesterol levels. Patients were randomized to usual therapy (n = 13) or to 10 to 20 mg of atorvastatin (n = 12). Control subjects received niacin when their low-density lipoprotein (LDL) cholesterol levels were >130 mg/dl (n = 4). Neointimal hyperplasia by intracoronary ultrasonography, endothelial dependent vascular reactivity, and coronary flow reserve were measured at baseline and 1 year. Control group total cholesterol (203 +/- 11 to 200 +/- 13 mg/dl) and LDL (116 +/- 10 to 119 +/- 11 mg/dl) remained stable, whereas there was a nonsignificant reduction at 12 months in the atorvastatin group (total cholesterol 216 +/- 28 to 178 +/- 21 mg/dl; LDL 126 +/- 17 to 100 +/- 18 mg/dl). At 2 to 3 months there was a significant increase in total cholesterol and LDL cholesterol that was reduced with atorvastatin. At 1 year, patients taking atorvastatin showed a decrease in new or progressing lesions (2.5 +/- 1.7 vs 4.2 +/- 1.8 lesions/patient, p = 0.02), progression of maximal intimal thickness (0.12 +/- 0.07 vs 0.52 +/- 0.17 mm, p = 0.04), and percent area stenosis (5.9 +/- 2.2% vs 19.0 +/- 5.5%, p = 0.04). Atorvastatin ameliorated progressive endothelial dysfunction, whereas coronary flow reserve was unchanged in both groups. Atorvastatin administered to patients with normal or mild hypercholesterolemia in the initial year after transplant reduced the initial increase in LDL cholesterol, and, by doing so, prevented the development and progression of coronary artery lesions and endothelial dysfunction with only mild long-term decreases in cholesterol levels.
Therapeutic hypothermia and temperature management | 2012
Mariana R Gonzalez; Emily C Esposito; Marion Leary; David F. Gaieski; Daniel M. Kolansky; Gene Chang; Lance B. Becker; Brendan G. Carr; Anne V. Grossestreuer; Benjamin S. Abella
Urgent coronary angiography following cardiac arrest is an important consideration as part of a therapeutic hypothermia/postresuscitation care bundle. Few data exist to guide the selection of patients who should receive postarrest angiography. This investigation sought to evaluate patient-level variables on initial postarrest presentation and their association with significant coronary lesions on subsequent angiography. Clinical and angiographic data were collected on consecutive postarrest patients from July 2007 to April 2012 who underwent coronary angiography during hospitalization. Univariate and multivariable analyses were performed to determine the relationship between patient characteristics, clinical data, and the outcome measure, defined as the presence of at least one coronary lesion with >75% stenosis. Of 527 cardiac arrest patients, 267 achieved return of spontaneous circulation; 106 of these initial survivors received coronary angiography. This cohort had a mean age of 58.1±13.5 years and a survival to discharge of 73/106 (69%), with therapeutic hypothermia utilized in 79/106 (75%) patients. Significant coronary lesions were found on angiography in 68/106 (64%) patients. Multivariable adjusted analysis demonstrated that significant lesions were associated with a prior known history of coronary disease and/or prior myocardial infarction (odds ratio [OR] 6.2, 95% confidence interval [CI] 1.6-24.4, p=0.009), and with initial rhythm of ventricular fibrillation/ventricular tachycardia (OR 2.9, 95% CI 1.1-7.7, p=0.033), but not with hypertension, tobacco use, age, or initial troponin measurements. Prior known history of coronary disease and a shockable arrest rhythm were associated with significant coronary lesions on subsequent angiography. Normal initial troponin values and younger age did not exclude clinically relevant lesions postarrest.
American Heart Journal | 2000
David DeNofrio; Shashank Desai; Daniel J. Rader; Gene Chang; Michael P. Kelley; Michael A. Acker; Evan Loh
BACKGROUND Elevated concentrations of lipoprotein(a) have been considered an important risk factor in the development of premature cardiovascular disease and have been proposed as a risk factor in the development of accelerated cardiac allograft vasculopathy after orthotopic heart transplantation. METHODS We prospectively measured lipoprotein(a), fasting cholesterol, and triglyceride concentrations before (n = 38), 6 months (n = 38), and 1 year (n = 21) after orthotopic heart transplantation. The mean age of the patients was 52 +/- 2 years. Eighty-seven percent of the patients were men, 82% were white, and 61% had ischemic cardiomyopathy. RESULTS Mean lipoprotein(a) concentration was lower 6 months after transplantation than it was before the operation (23 +/- 3 mg/dL vs 17 +/- 3 mg/dL; P =.014) and remained low 1 year after transplantation (23 +/- 3 mg/dL vs 18 +/- 4 mg/dL; P = not significant). In contrast, mean cholesterol concentration was higher 6 months after transplantation (171 +/- 8 mg/dL vs 221 +/- 8 mg/dL; P <.001) and 1 year (171 +/- 8 mg/dL vs 205 +/- 10 mg/dL; P <.01) than it was before transplantation. Triglyceride concentration was higher 1 year after transplantation than it was before the operation (146 +/- 13 mg/dL vs 184 +/- 20 mg/dL; P =.017). CONCLUSIONS Lipoprotein(a) concentrations decrease during the 6 months after transplantation and stay low for at least 1 year after the operation. Additional studies are needed to ascertain the effect these changes in lipoprotein(a) concentration on the development of cardiac allograft vasculopathy.
American Heart Journal | 1998
Gene Chang; David DeNofrio; Shashank Desai; Michael P. Kelley; Daniel J. Rader; Michael A. Acker; Evan Loh
Transplantation | 1999
Gene Chang; Robert L. Wilensky; Evan Loh; Vincent See; Andrew Kao; Michael A. Acker; David DeNofrio
Archive | 2000
David DeNofrio; Shashank Desai; Daniel J. Rader; Gene Chang; Michael P. Keby; A. Acker; Evan Lob
Circulation | 2011
Mariana R Gonzalez; Marion Leary; Emily C Esposito; David F. Gaieski; Daniel M. Kolansky; Brendan G. Carr; Gene Chang; Lance B. Becker; Benjamin S. Abella
Cardiovascular reviews and reports | 2001
Gene Chang; Howard C. Herrmann