Ernst Schwarz - Academia.edu (original) (raw)
Papers by Ernst Schwarz
Journal of thrombosis and thrombolysis, 2001
Behcet's disease (BD) is a rare systemic inflammatory disease of unknown aetiology with a var... more Behcet's disease (BD) is a rare systemic inflammatory disease of unknown aetiology with a variety of organ manifestations. A case of Behcet's disease complicated by deep vein thrombosis (DVT) and inferior vena cava thrombosis referred to our institution is reported. In addition, a structured literature search using the methodology of evidence-based medicine for the localization of venous lesions, treatment modalities, and outcome of patients with Behcet's disease and concurrent thrombosis was performed. A modified validity score was assigned by established methods. In total, 214 citations were identified using our search strategy. Among these citations, 10 papers including a total of 32 patients (25 male, 7 female) met the inclusion criteria and were incorporated into this overview together with our patient. All studies consisted of serial case reports without control subjects. Neither localization of venous lesions, nor treatment modalities were homogeneous not allowing...
Journal of cardiovascular pharmacology and therapeutics, 1999
BACKGROUND: Congenital origin of the left coronary artery from the pulmonary artery (ALCAPA) resu... more BACKGROUND: Congenital origin of the left coronary artery from the pulmonary artery (ALCAPA) results in chronically dysfunctional myocardium with the partial ability to recover after revascularization. We attempted to establish an ALCAPA syndrome in anesthetized pigs for 24 hours and to compare it with stunned and infarcted myocardium. METHODS AND RESULTS: In group 1 (n = 12), a bypass graft was interposed between the pulmonary artery and the left anterior descending coronary artery (LAD). Reduction of flow in the LAD with gradual increases in flow from the pulmonary artery resulted in an incremental reduction of segment shortening (8.9 +/- 5.3% at 24 hours vs 26.6 +/- 10% at baseline, P <.005). In group 3 (n = 5), 2 cycles of 10-minute LAD occlusion resulted in decreased segment shortening with slow recovery (at 24 hours 18.7 +/- 1.3% vs 24.2 +/- 4% at baseline, segment shortening with slow recovery (at 24 hours 18.7 +/- 1.3% vs 24.2 +/- 4% at baseline, P <.05). In group 3 (n...
Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy, 1997
There is no agreement on the effect of angiotensin II receptor blockade in the setting of ischemi... more There is no agreement on the effect of angiotensin II receptor blockade in the setting of ischemic reperfusion. Our aim was to assess the acute effects of angiotensin-converting enzyme (ACE) inhibition and angiotensin II AT1-subtype receptor blockade in pig heart. Five groups of open-chest pigs received 1 hour of left anterior descending (LAD) coronary artery occlusion and 2 hours of reperfusion. Left ventricular pressure was monitored by an intraventricular catheter, and regional segment shortening (%SS) in the LAD-supplied territory was measured by ultrasonic crystals implanted in the subendocardium. Group 1 (n = 6) served as the control; groups 2 (n = 6) and 3 (n = 6) received the angiotensin II receptor blocker, EXP 3174 (C22H21Cl1N6O2), and the ACE inhibitor, enalaprilat, respectively, prior to LAD occlusion; group 4 (n = 6) was preconditioned with two cycles of 10 minutes of coronary occlusion and 30 minutes of reperfusion; and group 5 (n = 6) underwent preconditioning with ad...
Journal of The American College of Cardiology, 2006
Chronic heart failure (HF) and erectile dysfunction (ED) are 2 highly prevalent disorders that fr... more Chronic heart failure (HF) and erectile dysfunction (ED) are 2 highly prevalent disorders that frequently occur concomitantly. Coronary artery disease, HF, and ED share several common risk factors, including diabetes mellitus, hypertension, smoking, and dyslipidemia. Additionally, the distinct physiologic sequelae of HF create unique organic and psychologic factors contributing to ED in this patient population. Standard HF therapy with beta-receptor blockers, digoxin and thiazide diuretics may worsen sexual dysfunction owing to medication side effects. This may, in turn, lead to noncompliance in misguided efforts to retain satisfactory sexual activity, with secondary worsening of cardiac capacity. This review describes the unique aspects of ED in the HF population.
International Journal of Impotence Research, 2008
Sexual dysfunction is a common problem of increasing incidence that is associated with multiple c... more Sexual dysfunction is a common problem of increasing incidence that is associated with multiple co-morbid conditions and chronic diseases. In heart failure, however, exact numbers are unknown, in part secondary to under-reporting and under-interrogating by health care providers. A gender-specific questionnaire was modified from established sexual dysfunction questionnaires to correspond to a non-randomized outpatient heart failure population, to assess the
Tissue Engineering, 2004
Studies have demonstrated the feasibility of transplanting cardiomyocytes after myocardial infarc... more Studies have demonstrated the feasibility of transplanting cardiomyocytes after myocardial infarction (MI). However, persistence and effects on left ventricular (LV) function have not been elucidated in long-term studies. Ventricular fetal cardiomyocytes from embryos of both sexes were injected into marginal regions of MI 4 weeks after suture occlusion of the left anterior descending artery in adult female rats. Two and 6 months after transplantation (Tx), engrafted cells were traced by immunohistochemical in situ hybridization for Y chromosomes or bromodeoxyuridine (BrdU) staining, LV dimensions and function were assessed by echocardiography, and LV pressure was assessed ex vivo in a Langendorff perfusion system. Immunohistochemistry for alpha-sarcomeric actin and Y chromosomes revealed the presence of transplanted cells in infarcted host myocardium at both 2 and 6 months. End-diastolic LV diameter markedly decreased after Tx and fractional shortening gradually increased after Tx (31.3 +/- 4.5% before Tx, 45.4 +/- 4.2% at 6 months; p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.005). Wall area fraction and MI size were unaffected by Tx. In hearts with MI, but not in normal hearts, Tx led to the development of higher pressures (87 +/- 18 versus 38 +/- 8 mmHg, 6 months post-Tx versus nontreated). After catecholamine stimulation, both infarcted and normal hearts developed higher pressures after Tx (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.005), ultimately associated with reduced mortality after Tx versus nontreated. Transplanted cardiomyocyte-rich graft cells persist in host myocardium and mediate continuous improvement of LV function and survival in a rat model of MI even during long-term follow-up, possibly involving a catecholamine-sensitive mechanism.
Pathology - Research and Practice, 2001
Toxoplasma gondii infections in heart transplant recipients emerge in most cases as newly acquire... more Toxoplasma gondii infections in heart transplant recipients emerge in most cases as newly acquired infections of the immunocompromised sero-negative patient from an exogenous source, usually the donor organ. We report on a 64-year-old heart transplant recipient who developed pneumonitis, myocarditis, and hyperacute encephalitis three weeks after transplantation. Histopathological examination of an endomyocardial biopsy revealed fulminant T. gondii infection. Although appropriate chemotherapy was administered immediately, the patient died the next day. Our case demonstrates that if a histological diagnosis is not rendered in time, fulminant toxoplasmosis may lead to a fatal outcome. In conclusion, a general screening of the donors and recipients for opportunistic infections, including toxoplasmosis, and an appropriate prophylaxis should always be considered.
Journal of the American College of Cardiology, 1996
We sought to define the effects of short-term beta-adrenergic blocking medication on intracoronar... more We sought to define the effects of short-term beta-adrenergic blocking medication on intracoronary flow characteristics, clinical symptoms and angiographic diameter changes in patients with severe myocardial bridging of the left anterior descending coronary artery. Controversy exists regarding the pathophysiology, clinical relevance and optimal therapy in symptomatic patients with myocardial bridges because antianginal drugs have not been systematically tested. In 15 symptomatic patients with myocardial bridging of the left anterior descending coronary artery, maximal lumen diameter reductions were evaluated by quantitative coronary angiography. There were no angiographic signs of coronary artery disease. Coronary blood flow velocities (using a 0.014-in. [0.035 cm] Doppler guide wire) were measured at rest, during atrial pacing and during intravenous administration of a short-acting beta-blocker (esmolol, 50 to 500 micrograms/kg body weight per min) with continuous atrial pacing. The maximal angiographic systolic lumen diameter reduction within the myocardial bridges was 83 +/- 9% at rest, with a persistent diastolic diameter reduction of 41 +/- 11% (mean +/- SD). Short-term intravenous beta-blocker therapy decreased the diameter reduction during both systole (from 83 +/- 9% to 62 +/- 11%) and diastole (from 41 +/- 11% to 30 +/- 9%, both p < 0.001). The average diastolic peak flow velocity was higher within the myocardial bridges (33 +/- 13 cm/s) than the proximal (26 +/- 13 cm/s) and distal bridges (17 +/- 4 cm/s, both p < 0.001). During tachypacing, average diastolic peak flow velocity increased within the bridged segments to 63 +/- 21 cm/s versus 29 +/- 12 cm/s in the proximal and 20 +/- 4 cm/s in the distal bridges (both p < 0.001). Beta-receptor blockade produced a return to baseline values (average diastolic peak flow velocity within bridge 35 +/- 16 cm/s, p < 0.001). ST segment changes and symptoms were abolished with beta-blocker administration. In patients with myocardial bridges, administration of short-acting beta-blockers during atrial pacing alleviates anginal symptoms and signs of ischemia. This effect was mediated by a reduction of vascular compression and maximal flow velocities within the bridged coronary artery segment.
Journal of the American College of Cardiology, 2002
The aim of this study was to evaluate the coronary blood flow velocity pattern immediately and 24... more The aim of this study was to evaluate the coronary blood flow velocity pattern immediately and 24 h after percutaneous transluminal coronary angioplasty (PTCA) for acute myocardial infarction (AMI) in relation to myocardial reperfusion and follow-up left ventricular (LV) function. BACKGROUND Analysis of coronary blood flow velocity pattern after AMI may provide information about microvascular damage and the occurrence of a reperfusion injury.
Journal of the American College of Cardiology, 2000
The effects of direct intramyocardial injection of the plasmid encoding vascular endothelial grow... more The effects of direct intramyocardial injection of the plasmid encoding vascular endothelial growth factor (phVEGF 165 ) in the border zone of myocardial infarct tissue in rat hearts were investigated.
Journal of the American College of Cardiology, 1998
We sought to define the effects of time on contractile function, morphology and functional recove... more We sought to define the effects of time on contractile function, morphology and functional recovery after coronary revascularization in patients with dysfunctional but viable (hibernating) myocardium. Functional recovery after coronary artery bypass graft surgery in patients with chronic myocardial hibernation is incomplete or delayed. The proposed cause is a progressive temporal degeneration of cardiomyocytes. In 32 patients with multivessel coronary disease, regional wall motion analysis was performed in hypoperfused but metabolically active areas before and 6 months after bypass surgery. During bypass surgery, transmural biopsy samples were obtained from the center of the hypokinetic zone for light and electron microscopic analyses. The proposed duration of myocardial hibernation was retrospectively assessed. Patients with a subacute hibernating condition (<50 days) demonstrated a higher preoperative ejection fraction (EF, 50+/-8%), and a better preserved wall motion (WM) in the supraapical wall (-1.4+/-0.4) than did patients with intermediate-term (>50 days, EF 37+/-9%, p < 0.05; WM -2.4+/-1.5, p = 0.08) or chronic (>6 months, EF 40+/-14%, WM -2.7+/-0.9, p < 0.005) ischemia. Structural degeneration correlated with the duration of ischemia (r = 0.56, p < 0.05). Postoperative recovery of function was enhanced in patients with a short history of hibernation compared with patients with an intermediate-term or chronic condition (EF 60+/-10% vs. 40+/-10%, p < 0.001, and vs. 47+/-14%, p < 0.05). Hibernating myocardium exhibits time-dependent deterioration due to progressive structural degeneration with enhanced fibrosis. Early revascularization should be attempted to salvage the jeopardized tissue and improve postoperative outcome.
Journal of the American College of Cardiology, 1996
Journal of the American College of Cardiology, 2002
Intravenous myocardial contrast echocardiography (MCE) has been used to demonstrate the degree of... more Intravenous myocardial contrast echocardiography (MCE) has been used to demonstrate the degree of micrevascular damage in patients with acute myocardial infarction (AMI) treated by primary transtuminal coronary angioplasty (PTCA). We hypothesized that the degree of reperfusion as shown by MCE relates to the coronary flow velocity pattern (CFVP) in the infarct related artery after PTCA for AMI.
International Journal of Impotence Research, 2005
Erectile dysfunction (ED) is increasingly considered as one manifestation of systemic vascular di... more Erectile dysfunction (ED) is increasingly considered as one manifestation of systemic vascular disease. Accordingly, ED and coronary artery disease share mutual risk factors and frequently coexist. Sexual health is an important aspect of our patients' lives, and ED is a common concern of the cardiovascular patient. Despite this, sexual function is under-addressed in the cardiac patient. Even when this topic is broached by the primary care physician or urologist, ED frequently remains untreated due to safety concerns involving cardiac disease and other comorbidities. This article describes our experience with this unique patient population, as well as our approach to building a multidisciplinary clinic designed to specifically address the important issue of ED in the cardiac patient.
International Journal of Impotence Research, 2007
Phosphodiesterase-5 (PDE-5) inhibitors selectively inhibit PDE-5 enzymes that are present in vari... more Phosphodiesterase-5 (PDE-5) inhibitors selectively inhibit PDE-5 enzymes that are present in various tissues like penile tissue, platelets, vascular, and smooth muscle tissue. The drug's actions on these tissues have lead to the successful therapeutic use in patients suffering from conditions such as erectile dysfunction (ED) and pulmonary hypertension. PDE-5 inhibitors (PDE-5i) act on the erectile tissue causing penile smooth muscle relaxation and vasodilatation leading to penile erection. In addition, in particular when used in conjunction with prostaglandin inhibitors, PDE-5i cause vasodilatation in pulmonary vasculature hence decreasing both the pulmonary arterial pressure and resistance. PDE-5i have also shown to mildly decrease blood pressure, increase cardiac index, and increase coronary blood flow in experimental animals as well as in human studies. The Food and Drug Administration (FDA) has approved three PDE-5i for the treatment of ED: sildenafil (Viagra), vardenafil (Levitra), and tadalafil (Cialis) and one for pulmonary hypertension: sildenafil (Revatio). These agents are highly selective for PDE-5 enzymes as compared to other subclasses of PDE enzymes and have the almost identical pharmacological action but slightly different pharmacokinetics. Only little data exist about long-term use of PDE-5i and their effects on different organ system. This paper reviews the current information available on chronic PDE-5 inhibitor use.
Clinical Cardiology, 2009
Background: There is controversy regarding the potential effects of statin therapy on mortality i... more Background: There is controversy regarding the potential effects of statin therapy on mortality in patients with heart failure. The present study analyzed the possible effects of statin therapy on morbidity and mortality in patients with diastolic heart failure over long-term follow-up. Hypothesis: To evaluate potential effect of statin therapy on hospitalization rate and mortality in patients with diastolic heart failure. Methods: Patients with preserved left ventricular ejection fraction (≥50%), hospitalized for clinical symptoms of heart failure were evaluated. Patients on statin therapy started at or prior to their first heart failure admission represented group 1 and patients without statin therapy represented group 2. The effects of statins on hospitalization rates and mortality were assessed during a 5 year follow-up. Results: A total of 270 patients (group 1 n = 81; group 2 n = 189) were followed over 5 years. Patients on statins demonstrated improved survival compared to patients without statin therapy (hazard ratio [HR] = 0.65, 95% confidence interval [CI]: 0.45-0.95, P = .029). The survival benefit was maintained after adjusting for differences in baseline characteristics, comorbidities, and other medications. There was no significant difference in the mean cardiovascular hospitalization rate (3.0 ± 3.2 vs 3.8 ± 4.7, P = .23) and in overall hospitalization rate (7.1 ± 6.3 vs 7.8 ± 7.7, P = .52) between groups 1 and 2, respectively. Conclusion: Statin therapy appears to be associated with improved survival in patients with diastolic heart failure.
Cardiology, 2009
There is no widely accepted classification to guide therapy in patients with symptomatic myocardi... more There is no widely accepted classification to guide therapy in patients with symptomatic myocardial bridging (MB). A retrospective analysis of 157 patients with chest pain, angiographic MB of the left anterior descending artery without obstructive coronary artery disease (CAD) was performed. Patients were evaluated for clinical symptoms, objective signs of ischemia by stress test, intracoronary Doppler flow measurement and coronary flow reserve. 100 patients without CAD or MB served as controls. There was no difference in clinical symptoms and objective signs of ischemia between controls and patients with MB. The length of MB was 22.6 +/- 7.8 mm, maximal systolic luminal diameter reduction 71 +/- 16%, and maximal mid-diastolic luminal reduction 34.7 +/- 13% as demonstrated by quantitative coronary angiography (QCA). Intracoronary Doppler showed significantly increased average peak flow velocity (APV), average systolic peak velocity (ASPV), average diastolic peak flow velocity (ADPV), and maximal peak velocity (MPV) in MB versus proximal and distal segments at rest and after maximal vasodilatation (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001 for all parameters). Coronary flow reserve was significantly higher proximally (2.9 +/- 0.9) compared with segments distal to the MB (2.0 +/- 0.6, p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01). We propose a new MB classification for symptomatic patients with MB:Type A:incidental finding on angiography, no objective signs of ischemia; Type B: objective signs of ischemia, and Type C: with or without objective signs of ischemia and altered intracoronary hemodynamics (by QCA/CFR/intracoronary Doppler). 5-Year follow-up data based on this classification showed that types B and C responded well to beta-blockers or calcium channel antagonists. Patients with type C refractory to medical therapy were treated with stenting of the MB. Patients with MB without CAD did not have a higher prevalence of chest pain or abnormal non-invasive stress tests compared to patients without CAD or MB. Intracoronary hemodynamic measurement is a novel approach that may be valuable in defining the functional significance of MB. We propose a classification of symptomatic patients with MB without CAD using non-invasive and invasive parameters to guide therapeutic choices.
Journal of cardiovascular pharmacology and therapeutics, 2009
Early studies in different stress models have shown potential beneficial effects of exogenous zin... more Early studies in different stress models have shown potential beneficial effects of exogenous zinc application with reduction in the rate of apoptotic cell death. This has not been shown in models of myocardial infarction. Rats were exposed to either brief episodes of acute ischemia followed by reperfusion (phase 1) or chronic coronary occlusion (phase 2). Animals were either treated with zinc or vehicle. Groups 1 and 3 received zinc-bis-(DL-hydrogenaspartate) 10 mg/kg body weight as a single 5-mL bolus administered intraperitoneally 24 hours prior to coronary occlusion, groups 2 and 4 received saline. The infarct sizes were determined by triphenyltetrazolium chloride staining and expressed at relative areas to areas of ischemia. Histological slices of the rat's myocardium at the border zones of the infarcts were stained with the TUNEL method to assess for apoptosis. Animals in groups 5, 7, and 9 received zinc, given once before and then repeated every 4 days after coronary occl...
Journal of cardiovascular pharmacology and therapeutics, 2008
A large number of heart transplants are performed annually in different transplant centers in the... more A large number of heart transplants are performed annually in different transplant centers in the United States. This is partly because of the improved survival of patients who undergo cardiac transplantation, thus making it a more viable option in the management of end-stage heart failure. The survival benefit after heart transplantation is a result of newer immunosuppressive drug regimens and a better understanding of their effects and interactions. Several studies, mostly involving a small number of patients, describe use and comparison of the many distinct immunosuppressive drugs available to date. Interestingly, many transplant centers perform in-house typical induction treatment regimens because of their own experience and intra-institutional preference. This review summarizes current practices of immunosuppressive drug therapy in the first year post-heart transplant based on the available clinical evidence and discusses future options of heart transplant immunosuppressive dru...
Journal of cardiovascular pharmacology and therapeutics, 1998
BACKGROUND: Controversy exists concerning the duration of infarct size reduction with ischemic pr... more BACKGROUND: Controversy exists concerning the duration of infarct size reduction with ischemic preconditioning in different species. In the present study, we (a) evaluated the time course of protection with preconditioning and (b) sought to determine whether late protection (the "second window") after 24 hours is manifest in the open-chest pig model. METHODS AND RESULTS: Six groups of pentobarbital-anesthetized pigs underwent 1 hour of left anterior descending coronary artery occlusion and 2 hours of reperfusion. Group 1 served as control, and pigs in group 2 received two 10-minute episodes of preconditioning ischemia followed by 30 minutes of reperfusion before the sustained 1-hour occlusion. In groups 3-6, the period of intervening reperfusion between the preconditioning stimulus and the index ischemia was extended to 60, 90, and 300 minutes and 24 hours, respectively. The area at risk was determined by fluorescein dye injection, and infarct size was measured by incubati...
Journal of thrombosis and thrombolysis, 2001
Behcet's disease (BD) is a rare systemic inflammatory disease of unknown aetiology with a var... more Behcet's disease (BD) is a rare systemic inflammatory disease of unknown aetiology with a variety of organ manifestations. A case of Behcet's disease complicated by deep vein thrombosis (DVT) and inferior vena cava thrombosis referred to our institution is reported. In addition, a structured literature search using the methodology of evidence-based medicine for the localization of venous lesions, treatment modalities, and outcome of patients with Behcet's disease and concurrent thrombosis was performed. A modified validity score was assigned by established methods. In total, 214 citations were identified using our search strategy. Among these citations, 10 papers including a total of 32 patients (25 male, 7 female) met the inclusion criteria and were incorporated into this overview together with our patient. All studies consisted of serial case reports without control subjects. Neither localization of venous lesions, nor treatment modalities were homogeneous not allowing...
Journal of cardiovascular pharmacology and therapeutics, 1999
BACKGROUND: Congenital origin of the left coronary artery from the pulmonary artery (ALCAPA) resu... more BACKGROUND: Congenital origin of the left coronary artery from the pulmonary artery (ALCAPA) results in chronically dysfunctional myocardium with the partial ability to recover after revascularization. We attempted to establish an ALCAPA syndrome in anesthetized pigs for 24 hours and to compare it with stunned and infarcted myocardium. METHODS AND RESULTS: In group 1 (n = 12), a bypass graft was interposed between the pulmonary artery and the left anterior descending coronary artery (LAD). Reduction of flow in the LAD with gradual increases in flow from the pulmonary artery resulted in an incremental reduction of segment shortening (8.9 +/- 5.3% at 24 hours vs 26.6 +/- 10% at baseline, P <.005). In group 3 (n = 5), 2 cycles of 10-minute LAD occlusion resulted in decreased segment shortening with slow recovery (at 24 hours 18.7 +/- 1.3% vs 24.2 +/- 4% at baseline, segment shortening with slow recovery (at 24 hours 18.7 +/- 1.3% vs 24.2 +/- 4% at baseline, P <.05). In group 3 (n...
Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy, 1997
There is no agreement on the effect of angiotensin II receptor blockade in the setting of ischemi... more There is no agreement on the effect of angiotensin II receptor blockade in the setting of ischemic reperfusion. Our aim was to assess the acute effects of angiotensin-converting enzyme (ACE) inhibition and angiotensin II AT1-subtype receptor blockade in pig heart. Five groups of open-chest pigs received 1 hour of left anterior descending (LAD) coronary artery occlusion and 2 hours of reperfusion. Left ventricular pressure was monitored by an intraventricular catheter, and regional segment shortening (%SS) in the LAD-supplied territory was measured by ultrasonic crystals implanted in the subendocardium. Group 1 (n = 6) served as the control; groups 2 (n = 6) and 3 (n = 6) received the angiotensin II receptor blocker, EXP 3174 (C22H21Cl1N6O2), and the ACE inhibitor, enalaprilat, respectively, prior to LAD occlusion; group 4 (n = 6) was preconditioned with two cycles of 10 minutes of coronary occlusion and 30 minutes of reperfusion; and group 5 (n = 6) underwent preconditioning with ad...
Journal of The American College of Cardiology, 2006
Chronic heart failure (HF) and erectile dysfunction (ED) are 2 highly prevalent disorders that fr... more Chronic heart failure (HF) and erectile dysfunction (ED) are 2 highly prevalent disorders that frequently occur concomitantly. Coronary artery disease, HF, and ED share several common risk factors, including diabetes mellitus, hypertension, smoking, and dyslipidemia. Additionally, the distinct physiologic sequelae of HF create unique organic and psychologic factors contributing to ED in this patient population. Standard HF therapy with beta-receptor blockers, digoxin and thiazide diuretics may worsen sexual dysfunction owing to medication side effects. This may, in turn, lead to noncompliance in misguided efforts to retain satisfactory sexual activity, with secondary worsening of cardiac capacity. This review describes the unique aspects of ED in the HF population.
International Journal of Impotence Research, 2008
Sexual dysfunction is a common problem of increasing incidence that is associated with multiple c... more Sexual dysfunction is a common problem of increasing incidence that is associated with multiple co-morbid conditions and chronic diseases. In heart failure, however, exact numbers are unknown, in part secondary to under-reporting and under-interrogating by health care providers. A gender-specific questionnaire was modified from established sexual dysfunction questionnaires to correspond to a non-randomized outpatient heart failure population, to assess the
Tissue Engineering, 2004
Studies have demonstrated the feasibility of transplanting cardiomyocytes after myocardial infarc... more Studies have demonstrated the feasibility of transplanting cardiomyocytes after myocardial infarction (MI). However, persistence and effects on left ventricular (LV) function have not been elucidated in long-term studies. Ventricular fetal cardiomyocytes from embryos of both sexes were injected into marginal regions of MI 4 weeks after suture occlusion of the left anterior descending artery in adult female rats. Two and 6 months after transplantation (Tx), engrafted cells were traced by immunohistochemical in situ hybridization for Y chromosomes or bromodeoxyuridine (BrdU) staining, LV dimensions and function were assessed by echocardiography, and LV pressure was assessed ex vivo in a Langendorff perfusion system. Immunohistochemistry for alpha-sarcomeric actin and Y chromosomes revealed the presence of transplanted cells in infarcted host myocardium at both 2 and 6 months. End-diastolic LV diameter markedly decreased after Tx and fractional shortening gradually increased after Tx (31.3 +/- 4.5% before Tx, 45.4 +/- 4.2% at 6 months; p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.005). Wall area fraction and MI size were unaffected by Tx. In hearts with MI, but not in normal hearts, Tx led to the development of higher pressures (87 +/- 18 versus 38 +/- 8 mmHg, 6 months post-Tx versus nontreated). After catecholamine stimulation, both infarcted and normal hearts developed higher pressures after Tx (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.005), ultimately associated with reduced mortality after Tx versus nontreated. Transplanted cardiomyocyte-rich graft cells persist in host myocardium and mediate continuous improvement of LV function and survival in a rat model of MI even during long-term follow-up, possibly involving a catecholamine-sensitive mechanism.
Pathology - Research and Practice, 2001
Toxoplasma gondii infections in heart transplant recipients emerge in most cases as newly acquire... more Toxoplasma gondii infections in heart transplant recipients emerge in most cases as newly acquired infections of the immunocompromised sero-negative patient from an exogenous source, usually the donor organ. We report on a 64-year-old heart transplant recipient who developed pneumonitis, myocarditis, and hyperacute encephalitis three weeks after transplantation. Histopathological examination of an endomyocardial biopsy revealed fulminant T. gondii infection. Although appropriate chemotherapy was administered immediately, the patient died the next day. Our case demonstrates that if a histological diagnosis is not rendered in time, fulminant toxoplasmosis may lead to a fatal outcome. In conclusion, a general screening of the donors and recipients for opportunistic infections, including toxoplasmosis, and an appropriate prophylaxis should always be considered.
Journal of the American College of Cardiology, 1996
We sought to define the effects of short-term beta-adrenergic blocking medication on intracoronar... more We sought to define the effects of short-term beta-adrenergic blocking medication on intracoronary flow characteristics, clinical symptoms and angiographic diameter changes in patients with severe myocardial bridging of the left anterior descending coronary artery. Controversy exists regarding the pathophysiology, clinical relevance and optimal therapy in symptomatic patients with myocardial bridges because antianginal drugs have not been systematically tested. In 15 symptomatic patients with myocardial bridging of the left anterior descending coronary artery, maximal lumen diameter reductions were evaluated by quantitative coronary angiography. There were no angiographic signs of coronary artery disease. Coronary blood flow velocities (using a 0.014-in. [0.035 cm] Doppler guide wire) were measured at rest, during atrial pacing and during intravenous administration of a short-acting beta-blocker (esmolol, 50 to 500 micrograms/kg body weight per min) with continuous atrial pacing. The maximal angiographic systolic lumen diameter reduction within the myocardial bridges was 83 +/- 9% at rest, with a persistent diastolic diameter reduction of 41 +/- 11% (mean +/- SD). Short-term intravenous beta-blocker therapy decreased the diameter reduction during both systole (from 83 +/- 9% to 62 +/- 11%) and diastole (from 41 +/- 11% to 30 +/- 9%, both p < 0.001). The average diastolic peak flow velocity was higher within the myocardial bridges (33 +/- 13 cm/s) than the proximal (26 +/- 13 cm/s) and distal bridges (17 +/- 4 cm/s, both p < 0.001). During tachypacing, average diastolic peak flow velocity increased within the bridged segments to 63 +/- 21 cm/s versus 29 +/- 12 cm/s in the proximal and 20 +/- 4 cm/s in the distal bridges (both p < 0.001). Beta-receptor blockade produced a return to baseline values (average diastolic peak flow velocity within bridge 35 +/- 16 cm/s, p < 0.001). ST segment changes and symptoms were abolished with beta-blocker administration. In patients with myocardial bridges, administration of short-acting beta-blockers during atrial pacing alleviates anginal symptoms and signs of ischemia. This effect was mediated by a reduction of vascular compression and maximal flow velocities within the bridged coronary artery segment.
Journal of the American College of Cardiology, 2002
The aim of this study was to evaluate the coronary blood flow velocity pattern immediately and 24... more The aim of this study was to evaluate the coronary blood flow velocity pattern immediately and 24 h after percutaneous transluminal coronary angioplasty (PTCA) for acute myocardial infarction (AMI) in relation to myocardial reperfusion and follow-up left ventricular (LV) function. BACKGROUND Analysis of coronary blood flow velocity pattern after AMI may provide information about microvascular damage and the occurrence of a reperfusion injury.
Journal of the American College of Cardiology, 2000
The effects of direct intramyocardial injection of the plasmid encoding vascular endothelial grow... more The effects of direct intramyocardial injection of the plasmid encoding vascular endothelial growth factor (phVEGF 165 ) in the border zone of myocardial infarct tissue in rat hearts were investigated.
Journal of the American College of Cardiology, 1998
We sought to define the effects of time on contractile function, morphology and functional recove... more We sought to define the effects of time on contractile function, morphology and functional recovery after coronary revascularization in patients with dysfunctional but viable (hibernating) myocardium. Functional recovery after coronary artery bypass graft surgery in patients with chronic myocardial hibernation is incomplete or delayed. The proposed cause is a progressive temporal degeneration of cardiomyocytes. In 32 patients with multivessel coronary disease, regional wall motion analysis was performed in hypoperfused but metabolically active areas before and 6 months after bypass surgery. During bypass surgery, transmural biopsy samples were obtained from the center of the hypokinetic zone for light and electron microscopic analyses. The proposed duration of myocardial hibernation was retrospectively assessed. Patients with a subacute hibernating condition (<50 days) demonstrated a higher preoperative ejection fraction (EF, 50+/-8%), and a better preserved wall motion (WM) in the supraapical wall (-1.4+/-0.4) than did patients with intermediate-term (>50 days, EF 37+/-9%, p < 0.05; WM -2.4+/-1.5, p = 0.08) or chronic (>6 months, EF 40+/-14%, WM -2.7+/-0.9, p < 0.005) ischemia. Structural degeneration correlated with the duration of ischemia (r = 0.56, p < 0.05). Postoperative recovery of function was enhanced in patients with a short history of hibernation compared with patients with an intermediate-term or chronic condition (EF 60+/-10% vs. 40+/-10%, p < 0.001, and vs. 47+/-14%, p < 0.05). Hibernating myocardium exhibits time-dependent deterioration due to progressive structural degeneration with enhanced fibrosis. Early revascularization should be attempted to salvage the jeopardized tissue and improve postoperative outcome.
Journal of the American College of Cardiology, 1996
Journal of the American College of Cardiology, 2002
Intravenous myocardial contrast echocardiography (MCE) has been used to demonstrate the degree of... more Intravenous myocardial contrast echocardiography (MCE) has been used to demonstrate the degree of micrevascular damage in patients with acute myocardial infarction (AMI) treated by primary transtuminal coronary angioplasty (PTCA). We hypothesized that the degree of reperfusion as shown by MCE relates to the coronary flow velocity pattern (CFVP) in the infarct related artery after PTCA for AMI.
International Journal of Impotence Research, 2005
Erectile dysfunction (ED) is increasingly considered as one manifestation of systemic vascular di... more Erectile dysfunction (ED) is increasingly considered as one manifestation of systemic vascular disease. Accordingly, ED and coronary artery disease share mutual risk factors and frequently coexist. Sexual health is an important aspect of our patients' lives, and ED is a common concern of the cardiovascular patient. Despite this, sexual function is under-addressed in the cardiac patient. Even when this topic is broached by the primary care physician or urologist, ED frequently remains untreated due to safety concerns involving cardiac disease and other comorbidities. This article describes our experience with this unique patient population, as well as our approach to building a multidisciplinary clinic designed to specifically address the important issue of ED in the cardiac patient.
International Journal of Impotence Research, 2007
Phosphodiesterase-5 (PDE-5) inhibitors selectively inhibit PDE-5 enzymes that are present in vari... more Phosphodiesterase-5 (PDE-5) inhibitors selectively inhibit PDE-5 enzymes that are present in various tissues like penile tissue, platelets, vascular, and smooth muscle tissue. The drug's actions on these tissues have lead to the successful therapeutic use in patients suffering from conditions such as erectile dysfunction (ED) and pulmonary hypertension. PDE-5 inhibitors (PDE-5i) act on the erectile tissue causing penile smooth muscle relaxation and vasodilatation leading to penile erection. In addition, in particular when used in conjunction with prostaglandin inhibitors, PDE-5i cause vasodilatation in pulmonary vasculature hence decreasing both the pulmonary arterial pressure and resistance. PDE-5i have also shown to mildly decrease blood pressure, increase cardiac index, and increase coronary blood flow in experimental animals as well as in human studies. The Food and Drug Administration (FDA) has approved three PDE-5i for the treatment of ED: sildenafil (Viagra), vardenafil (Levitra), and tadalafil (Cialis) and one for pulmonary hypertension: sildenafil (Revatio). These agents are highly selective for PDE-5 enzymes as compared to other subclasses of PDE enzymes and have the almost identical pharmacological action but slightly different pharmacokinetics. Only little data exist about long-term use of PDE-5i and their effects on different organ system. This paper reviews the current information available on chronic PDE-5 inhibitor use.
Clinical Cardiology, 2009
Background: There is controversy regarding the potential effects of statin therapy on mortality i... more Background: There is controversy regarding the potential effects of statin therapy on mortality in patients with heart failure. The present study analyzed the possible effects of statin therapy on morbidity and mortality in patients with diastolic heart failure over long-term follow-up. Hypothesis: To evaluate potential effect of statin therapy on hospitalization rate and mortality in patients with diastolic heart failure. Methods: Patients with preserved left ventricular ejection fraction (≥50%), hospitalized for clinical symptoms of heart failure were evaluated. Patients on statin therapy started at or prior to their first heart failure admission represented group 1 and patients without statin therapy represented group 2. The effects of statins on hospitalization rates and mortality were assessed during a 5 year follow-up. Results: A total of 270 patients (group 1 n = 81; group 2 n = 189) were followed over 5 years. Patients on statins demonstrated improved survival compared to patients without statin therapy (hazard ratio [HR] = 0.65, 95% confidence interval [CI]: 0.45-0.95, P = .029). The survival benefit was maintained after adjusting for differences in baseline characteristics, comorbidities, and other medications. There was no significant difference in the mean cardiovascular hospitalization rate (3.0 ± 3.2 vs 3.8 ± 4.7, P = .23) and in overall hospitalization rate (7.1 ± 6.3 vs 7.8 ± 7.7, P = .52) between groups 1 and 2, respectively. Conclusion: Statin therapy appears to be associated with improved survival in patients with diastolic heart failure.
Cardiology, 2009
There is no widely accepted classification to guide therapy in patients with symptomatic myocardi... more There is no widely accepted classification to guide therapy in patients with symptomatic myocardial bridging (MB). A retrospective analysis of 157 patients with chest pain, angiographic MB of the left anterior descending artery without obstructive coronary artery disease (CAD) was performed. Patients were evaluated for clinical symptoms, objective signs of ischemia by stress test, intracoronary Doppler flow measurement and coronary flow reserve. 100 patients without CAD or MB served as controls. There was no difference in clinical symptoms and objective signs of ischemia between controls and patients with MB. The length of MB was 22.6 +/- 7.8 mm, maximal systolic luminal diameter reduction 71 +/- 16%, and maximal mid-diastolic luminal reduction 34.7 +/- 13% as demonstrated by quantitative coronary angiography (QCA). Intracoronary Doppler showed significantly increased average peak flow velocity (APV), average systolic peak velocity (ASPV), average diastolic peak flow velocity (ADPV), and maximal peak velocity (MPV) in MB versus proximal and distal segments at rest and after maximal vasodilatation (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001 for all parameters). Coronary flow reserve was significantly higher proximally (2.9 +/- 0.9) compared with segments distal to the MB (2.0 +/- 0.6, p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01). We propose a new MB classification for symptomatic patients with MB:Type A:incidental finding on angiography, no objective signs of ischemia; Type B: objective signs of ischemia, and Type C: with or without objective signs of ischemia and altered intracoronary hemodynamics (by QCA/CFR/intracoronary Doppler). 5-Year follow-up data based on this classification showed that types B and C responded well to beta-blockers or calcium channel antagonists. Patients with type C refractory to medical therapy were treated with stenting of the MB. Patients with MB without CAD did not have a higher prevalence of chest pain or abnormal non-invasive stress tests compared to patients without CAD or MB. Intracoronary hemodynamic measurement is a novel approach that may be valuable in defining the functional significance of MB. We propose a classification of symptomatic patients with MB without CAD using non-invasive and invasive parameters to guide therapeutic choices.
Journal of cardiovascular pharmacology and therapeutics, 2009
Early studies in different stress models have shown potential beneficial effects of exogenous zin... more Early studies in different stress models have shown potential beneficial effects of exogenous zinc application with reduction in the rate of apoptotic cell death. This has not been shown in models of myocardial infarction. Rats were exposed to either brief episodes of acute ischemia followed by reperfusion (phase 1) or chronic coronary occlusion (phase 2). Animals were either treated with zinc or vehicle. Groups 1 and 3 received zinc-bis-(DL-hydrogenaspartate) 10 mg/kg body weight as a single 5-mL bolus administered intraperitoneally 24 hours prior to coronary occlusion, groups 2 and 4 received saline. The infarct sizes were determined by triphenyltetrazolium chloride staining and expressed at relative areas to areas of ischemia. Histological slices of the rat's myocardium at the border zones of the infarcts were stained with the TUNEL method to assess for apoptosis. Animals in groups 5, 7, and 9 received zinc, given once before and then repeated every 4 days after coronary occl...
Journal of cardiovascular pharmacology and therapeutics, 2008
A large number of heart transplants are performed annually in different transplant centers in the... more A large number of heart transplants are performed annually in different transplant centers in the United States. This is partly because of the improved survival of patients who undergo cardiac transplantation, thus making it a more viable option in the management of end-stage heart failure. The survival benefit after heart transplantation is a result of newer immunosuppressive drug regimens and a better understanding of their effects and interactions. Several studies, mostly involving a small number of patients, describe use and comparison of the many distinct immunosuppressive drugs available to date. Interestingly, many transplant centers perform in-house typical induction treatment regimens because of their own experience and intra-institutional preference. This review summarizes current practices of immunosuppressive drug therapy in the first year post-heart transplant based on the available clinical evidence and discusses future options of heart transplant immunosuppressive dru...
Journal of cardiovascular pharmacology and therapeutics, 1998
BACKGROUND: Controversy exists concerning the duration of infarct size reduction with ischemic pr... more BACKGROUND: Controversy exists concerning the duration of infarct size reduction with ischemic preconditioning in different species. In the present study, we (a) evaluated the time course of protection with preconditioning and (b) sought to determine whether late protection (the "second window") after 24 hours is manifest in the open-chest pig model. METHODS AND RESULTS: Six groups of pentobarbital-anesthetized pigs underwent 1 hour of left anterior descending coronary artery occlusion and 2 hours of reperfusion. Group 1 served as control, and pigs in group 2 received two 10-minute episodes of preconditioning ischemia followed by 30 minutes of reperfusion before the sustained 1-hour occlusion. In groups 3-6, the period of intervening reperfusion between the preconditioning stimulus and the index ischemia was extended to 60, 90, and 300 minutes and 24 hours, respectively. The area at risk was determined by fluorescein dye injection, and infarct size was measured by incubati...