Unprotected left main coronary artery stenting for cardiac allograft vasculopathy.

Cardiac allograft vasculopathy is the leading cause of death after the first year of transplantation. Treatment outcomes with medication, balloon angioplasty, bypass surgery, and retransplantation have been disappointing. We present our initial experience with stenting of the left main coronary artery in the setting of allograft vasculopathy.

Effective treatment of hyperhomocysteinemia in heart transplant recipients with and without renal failure.

BACKGROUND: Elevated total plasma homocysteine (tHcy) levels have been associated with vascular disease and higher mortality in patients with coronary artery disease. Graft coronary disease is a major cause of mortality in long-term survivors of heart transplantation, and hyperhomocysteinemia may be one of its causes. The objectives of our study were to establish the effectiveness of a 3 stage homocysteine-lowering algorithm in a group of 84 heart transplant (HTx) patients and to evaluate the effect of renal function on the response to homocysteine-lowering therapy. METHODS: Prospective treatment of 84 Htx patients (64 male; mean age, 48 +/- 13 years) with tHcy > 75th percentile consisted of a 3-stage treatment algorithm: Stage 1, folic acid (FA) 2 mg + vitamin (vit) B(12) 500 mcg daily; Stage 2, addition of vit B(6) 100 mg daily; Stage 3, increase FA to 15 mg daily. Serum creatinine (Cr) and tHcy levels were measured before treatment and 21 +/- 19 weeks after each stage of treatment. RESULTS: All 3 stages of treatment significantly lowered mean tHcy from 22.4 +/- 16.3 (mean +/- SD) micromol/liter to 16.3 +/- 6.7 micromol/liter (p < 0.00001), from 17.6 +/- 6.1 micromol/liter to 15.2 +/- 5.3 micromol/liter (p < 0.0001), and from 16.8 +/- 5.2 micromol/liter to 15.6 +/- 5.3 micromol/liter (p < 0.05), respectively. The average reduction from baseline was 38%. Creatinine levels did not change significantly during the study period. Total plasma homocysteine levels decreased below the 75th percentile in 55% of patients, with Cr levels significantly lower in this group of patients (126 +/- 36 micromol/liter vs 182 +/- 65 micromol/liter, p < 0.00001). However, we found no significant relationship between % change in tHcy and baseline Cr. CONCLUSIONS: In a group of 84 heart transplant patients with tHcy levels >75th percentile, treatment with FA and vit B(6) and B(12) according to a 3-stage algorithm resulted in statistically significant declines in mean tHcy levels. Overall, tHcy levels decreased 38%, with target tHcy levels <75th percentile achieved in 55% of the patients. The % change in tHcy was not related to Cr. Further studies are needed to correlate treatment of hyperhomocysteinemia with clinical endpoints, such as the time to development of transplant vasculopathy and long-term survival, and to define the most appropriate targets for therapy.

Management strategies for heparin-induced thrombocytopenia in heart-transplant candidates: case report and review of the literature.

Management of anticoagulation in patients with heparin-induced thrombocytopenia (HIT) undergoing surgery requiring cardiopulmonary bypass (CPB), such as cardiac transplantation, represents a difficult clinical problem and no clear management strategy exists. The cases of 2 patients with HIT who underwent cardiac transplantation using differing anticoagulation strategies are presented with a discussion of potential advantages and pitfalls of each approach used.

The enigma of recent onset dilated cardiomyopathy: what cause, what consequence, what control?

Acute onset dilated cardiomyopathy is a very common presentation encountered by cardiologists in clinical practice, but little is known about the etiology, pathophysiology, definitive diagnosis and management of this syndrome. The vast majority of cases are considered as idiopathic cardiomyopathy, or primary or secondary myocarditis, although rarely definitive diagnoses are obtained after extensive diagnostic procedures. Two scenarios are presented as a basis for a discussion of this challenging syndrome.

Effect of immunosuppressive therapy, serum creatinine, and time after transplant on plasma total homocysteine in patients following heart transplantation.

OBJECTIVES: To determine the prevalence of hyperhomocysteinemia in heart transplant recipients, and to assess the effect of renal function and immunosuppressive medication on total plasma homocysteine (tHcy) levels. BACKGROUND: Elevated plasma tHcy levels have been associated with increased risk of mortality in patients with established coronary artery disease. Graft coronary disease is the major cause of morbidity and mortality in long-term survivors of heart transplantation. The tHcy has been found to be elevated in heart and kidney transplant patients, however, the etiologic factors have not been clearly delineated. METHODS: The study group consisted of 70 heart transplant recipients (56 males, 14 females, mean age 53+/-13 years [range 17 to 69 years]). The parameters evaluated were fasting tHcy level, cumulative cyclosporine (CyA) dose, cumulative prednisone dose, serum creatinine, and time from transplantation. RESULTS: The mean fasting tHcy level was 20.5+/-10.2 micromol/L (range 5.2 to 59.0 micromol/L). Sixty-one (87%) had fasting tHcy levels greater than the seventy-fifth percentile of the general population (>12.2 micromol/L in males, and >10.1 micromol/L in females). There was no difference in mean post-transplant tHcy level between patients with and without coronary artery disease before transplantation (21.0+/-11.4 vs. 19.3+/-6.7 micromol/L, p = NS). There were significant relationships between the tHcy level and the serum creatinine (r = 0.76, p<0.001), and cumulative exposure to CyA (r = 0.31, p<0.01). There were no significant relationships between tHcy levels and cumulative prednisone dose, or time from transplantation. CONCLUSIONS: Fasting tHcy levels are markedly elevated in the majority of patients following heart transplantation, and are correlated to serum creatinine. Further studies are needed to determine other etiologic factors of elevated tHcy following heart transplantation, and to examine the impact of elevated tHcy on clinical outcomes.

The use of milrinone in pre-transplant assessment of patients with congestive heart failure and pulmonary hypertension.

BACKGROUND: Pulmonary hypertension in patients with congestive heart failure (CHF) is a risk factor for increased mortality after orthotopic cardiac transplantation. Reversibility of elevated pulmonary vascular resistance (PVR) by pharmacologic agents predicts improved outcomes. Milrinone, a phosphodiesterase inhibitor with vasodilating and positive inotropic properties, has been shown to lower PVR in one previous study. However, no study has documented outcomes after cardiac transplantation in patients in whom reversibility of pulmonary hypertension was demonstrated after administration of milrinone. METHODS: We retrospectively reviewed 19 patients with CHF and pulmonary hypertension defined as PVR > or = 3 Wood units, PVRI (pulmonary vascular resistance index) > or = 4 resistance units, or TPG (transpulmonary gradient = mean pulmonary artery pressure--mean capillary wedge pressure) > or = 12 mmHg being assessed for cardiac transplantation. A sub-group of 14 patients with severe pulmonary hypertension defined as PVR > or = 4, PVRI > or = 6 and TPG > or = 15 was also examined. Milrinone was administered as a bolus (50 ug/kg) and hemodynamic parameters were measured at 5, 10 and 15 minutes. Six patients received cardiac transplants. RESULTS: Administration of milrinone significantly lowered PVR, PVRI, mean pulmonary artery pressure (PAM)(all p = 0.002) and pulmonary capillary wedge pressure (PCWP)(p = 0.006). Cardiac output (CO) increased significantly (p = 0.001). TPG did not change (p = 0.33). In patients with severe pulmonary hypertension, the magnitude of these changes was greater. In addition, TPG was significantly lowered (p = 0.02). CONCLUSION: Milrinone lowered PVR by decreasing PAM and increasing CO significantly. In addition, PCWP was significantly lowered. These finding confirm both vasodilatory and inotropic effects of milrinone. Patients with severe pulmonary hypertension had more pronounced effects. There were no deaths in the group of patients proceeding to cardiac transplantation. Our study demonstrates the efficacy of milrinone in lowering PVR as well as suggesting safety in use in patients undergoing cardiac transplantation.

Left ventricular morphology in elite female resistance-trained athletes.

Long-term resistance training as performed by elite female resistance-trained athletes appears to be an insufficient stimulus to alter left ventricular cavity size, wall thickness, or estimated mass.

Aneurysmal subarachnoid hemorrhage associated with weight training: three case reports.

Weight training is a popular component of physical fitness in North America. This form of training remains relatively safe with few cases of life-threatening injuries. However, a series of studies have demonstrated that repetitive upper- and lower extremity weight training incorporating a Valsalva maneuver can increase arterial pressure to values as high as 480/350 mm Hg. This marked increase in arterial pressure is transmitted to the cerebral vasculature and increases cerebral arterial transmural pressure and may have the potential to initiate the rupture of a previously innocuous intracranial aneurysm. We report three cases of subarachnoid hemorrhage (SAH) associated with arm (bicep) curls and leg press weight training and discuss the possible link between this form of exercise and aneurysmal SAH.

Successful treatment of supraventricular tachycardia-induced cardiomyopathy with amiodarone: case report and review of literature.

Permanent junctional reciprocating tachycardia (PJRT) is a rare cause of supraventricular tachycardia in the pediatric population and is resistant to most pharmacological therapy. A case of supraventricular tachycardia that, on the basis of postnatal electrocardiographic and Holter monitor evidence, was diagnosed as PJRT and presented in utero as an atypical tachycardia with severe tachycardia-induced cardiomyopathy confirmed postnatally is presented. It is the only case of which the authors are aware that was controlled in the neonatal period by amiodarone and that resulted in complete resolution of systolic dysfunction. The literature discussing how tachycardia may induce cardiomyopathy and the use of amiodarone in treatment both pre- and postnatally are reviewed.

Molecular analysis provides evidence for human to human transmission of Staphylococcus aureus endocarditis in non-drug abusers.

Two cases of invasive Staphylococcus aureus are reported in which human to human transmission resulted in primary bacteremia and endocarditis. The identity of the organism was confirmed by phage typing, antibiograms, coagulase gene polymorphisms and ribotyping. This is the first documented case of such transmission not involving an intravenous drug abuser.

Aneurysm of the membranous ventricular septum producing subpulmonic outflow tract obstruction.

The authors report the case of a 31-year-old asymptomatic male who, following investigations for cardiac murmur, was found to have congenitally corrected (status solitus of the atria, left looping of the ventricles, leftward aorta in relation to the pulmonary artery [S,L,L]) transposition of the great vessels with significant right-sided ventricular outflow tract obstruction due to a large aneurysm of the membranous ventricular septum. Diagnosis was made with transesophageal echocardiography and confirmed during corrective surgery. The authors review the literature with regard to aneurysms of the membranous ventricular septum and their association with congenital heart disease, and they discuss the use of noninvasive tests aiding the diagnosis.

Safety and clinical utility of combined intravenous dipyridamole/symptom-limited exercise stress test with thallium-201 imaging in patients with known or suspected coronary artery disease.

Dipyridamole-induced coronary hyperemia with 201Tl myocardial perfusion scintigraphy can detect ischemic regions in individuals unable to perform adequate exercise, but it has several limitations. Symptom-limited exercise supplementation to intravenous dipyridamole can potentially overcome them, but the safety and diagnostic accuracy for this combination has not been established. Between 1987 and 1991, 441 consecutive patients were assessed for combined symptom-limited exercise test preceded by i.v. dipyridamole. Clinical records could not be obtained for 37 patients, and 40 patients were not exercised because they were unable; therefore 384 patients (mean age 58 +/- 9.8 yr, 278 men) underwent symptom-limited exercise preceded by 0.56 mg/kg of dipyridamole and followed by planar 201Tl perfusion scintigraphy. Following dipyridamole infusion, systolic blood pressure fell by 10 +/- 14 mmHg and heart rate increased by 8 +/- 11 bpm. Adverse effects were experienced by 77 people (dizziness in 44; headache in 11; nausea in 9; syncope in 2 and chest pain in 11). Exercise heart rate was 69% +/- 16% of predicted maximum and ST shift was -0.9 +/- 0.9 mm. Following exercise, seven patients required aminophylline (four after dizziness, two after headache, one after chest pain), which was uniformly successful. There were no episodes of prolonged chest pain, MI, death or serious arrhythmia. Safety was maintained for people with severe triple coronary artery disease, the elderly (> 70 yr) and those with significant pulmonary disease. Sensitivity was 95% for at least one with > 70% luminal stenosis and 94% for at least one with > 40% luminal stenosis. Specificity was 28% and 53% respectively. The addition of a symptom-limited exercise test to i.v. dipyridamole is safe for all groups of patients referred for 201Tl study.

Contemporary medical management of left ventricular dysfunction and congestive heart failure.

OBJECTIVE: The primary purpose of this review was to address the following question: based on the best available evidence, what should be the current medical management of congestive heart failure (CHF)? DATA SOURCES: The major sources for this review were from searches of the English language literature, including computer and bibliography reviews, of all randomized, controlled clinical trials and overview analyses of positive inotropic agents, preload/afterload reduction agents and beta-blocker medications in CHF. STUDY SELECTION: The number of studies reviewed was approximately 40. The major criterion for selection was that the studies be of CHF patients in randomized controlled clinical trials, particularly with a mortality/survival endpoint. Additional clinical trials of nonmortality endpoints in CHF patients and mortality trials in non-CHF patients were also selected to support possible pathophysiological insights for future CHF trials. DATA EXTRACTION: The data, particularly for the accompanying tables, were initially extracted by a single reviewer using common qualitative guidelines as far as was possible within the different temporal, etiological and geographic frameworks of the original component studies. Conclusions are drawn from this data synthesis and from published overviews. DATA SYNTHESIS: Angiotensin converting enzyme (ACE) inhibition therapy is effective in reducing mortality and morbidity in severe left ventricular dysfunction and CHF. Other systemic vasodilators may also be beneficial. The effects of digitalis on survival and morbidity in CHF are presently uncertain, but should be resolved in the near future. Other inotropic agents, at least in the long term, are clinically detrimental. Diuretics decrease morbidity, but their effect on mortality in CHF remains unknown. Beta-blocker and magnesium therapy offer promise in CHF, but await definitive clinical trials evaluation. CONCLUSIONS: The current medical therapy of CHF should definitely include ACE inhibitors, probably diuretics and possibly other vasodilators. Further viable trials of promising new, and older heretofore under-evaluated, CHF therapies are needed. Additionally, innovative strategies are needed to deal with this disease which has an increasing prevalence. Two strategies, primary prevention of CHF and a 'Heart Function Clinic', are discussed.