Management of aortopulmonary collaterals in children following cardiac transplantation for complex congenital heart disease.

Background: Heart transplantation (HTx) is increasingly utilized as therapy for end-stage cyanotic congenital heart disease. This study investigates the presence and impact of aortopulmonary collaterals (APCs) associated with cyanotic heart disease on the early post-operative course of patients undergoing transplantation. High output cardiac failure due to residual aortopulmonary collaterals can affect outcome following heart transplantation.

Norepinephrine elicits beta2-receptor-mediated dilation of isolated human coronary arterioles.

Background: The exact role of adrenoceptors in norepinephrine (NE)-mediated regulation of the human coronary circulation has yet to be elucidated. Thus, the goals of this study were to characterize the adrenoceptors involved in the responses to NE in isolated human coronary arterioles and small arteries.

Methods And Results: Arterioles (n=39) and small arteries from the left ventricle of explanted human hearts were isolated and cannulated.

Regression of pulmonary arteriovenous malformations following heart transplantation.

Pulmonary arteriovenous malformations (PAVMs) can occur following caval to pulmonary artery connection, Glenn and/or Fontan procedure, leading to severe cyanosis and exercise intolerance. It is unknown whether these abnormalities regress or persist following heart transplantation (HTx). Twenty patients with failed Fontan or Glenn procedures were screened for PAVMs prior to HTx by contrast echocardiography, selective pulmonary angiography, and pulmonary venous desaturation.

Outcome after orthotopic cardiac transplantation in adults with congenital heart disease.

Background: Advances in surgical and medical management have greatly improved long-term survival rates in patients with congenital heart disease (CHD). As these patients reach adulthood, myocardial dysfunction can occur, leading to cardiac transplantation.

Methods And Results: We reviewed the pretransplantation and posttransplantation courses of 24 patients >18 years old (mean age, 26 years; range, 18 to 56 years) with CHD who received a transplant between January 1985 and September 1998.

Amlodipine promotes kinin-mediated nitric oxide production in coronary microvessels of failing human hearts.

Recently, we found that amlodipine can release nitric oxide (NO) from canine coronary microvessels, which raises the question of whether amlodipine can also promote coronary NO production in failing human hearts. The goal of this study was to define the effect of amlodipine on NO production in failing human hearts and to determine the role of kinins in the control of NO production induced by amlodipine. Six explanted human hearts with end-stage heart failure were obtained immediately at transplant surgery.

Incidence and outcome of primary Epstein-Barr virus infection and lymphoproliferative disease in pediatric heart transplant recipients.

Background: The objective of this study was to assess the relationship between Epstein-Barr virus (EBV) infection and posttransplantation lymphoproliferative disease (PTLD) in pediatric heart transplant recipients. EBV is implicated in the development of PTLD. However, the relationship between primary EBV infection and PTLD is not well understood.

Angiotensin-converting enzyme inhibitors promote nitric oxide production in coronary microvessels from failing explanted human hearts.

We have previously shown that nitric oxide (NO) release by the coronary circulation in the failing and nonfailing human heart is, in part, regulated by local kinin production in coronary microvessels. Angiotensin-converting enzyme (ACE) also known as kininase II, inactivates kinins. ACE inhibitors prevent kinin breakdown by ACE, thereby increasing the concentration of bradykinin (BK) and related kinins.

Biventricular assist device as a bridge to transplantation in a pediatric patient.

A 5 1/2-year-old boy with idiopathic cardiomyopathy and rapidly worsening hemodynamic parameters underwent placement of a biventricular assist device as a bridge to transplantation. Direct anastomoses to both the aorta and pulmonary artery with Dacron grafts attached to Carmeda-coated tubing facilitated the support period. Inflow was provided by right atrial appendage and left ventricular apex cannulas.

Regulation of nitric oxide production in human coronary microvessels and the contribution of local kinin formation.

Background: The goal of this study was to define the regulation of nitric oxide release by coronary microvessels from the failing and nonfailing human heart and to determine the role of local kinin production in the elaboration of nitric oxide by human coronary microvascular endothelium.

Methods And Results: Ten hearts from humans with end-stage heart failure and two hearts from patients without heart failure were harvested at the time of orthotopic cardiac transplantation. Microvessels were sieved and the production of nitrite was determined by the Griess reaction.

Heart transplantation in children with congenital heart disease.

Objectives: The aim of this study was to describe heart transplantation in children with congenital heart disease and to compare the results with those in children undergoing transplantation for other cardiac diseases.

Background: Reports describe decreased survival after heart transplantation in children with congenital heart disease compared with those with cardiomyopathy. However, transplantation is increasingly being considered in the surgical management of children with complex congenital heart disease.

Decreasing incidence of coronary disease in pediatric cardiac transplant recipients using increased immunosuppression.

Background: Coronary artery disease (CAD) is a limiting factor to long-term survival in cardiac transplant recipients, affecting from 30% to 50% of patients by 4 years after surgery. Can the incidence of CAD be lowered with augmentation of immunosuppression?

Methods And Results: We compared the incidence of CAD in our pediatric transplant population with nine potential risk factors, including immunosuppressive regimen. The study group consisted of 55 patients who survived more than 1 year (or to first angiogram) or had autopsies.

Absence of hypertension despite chronic marked elevations in plasma norepinephrine in conscious dogs.

To better define the mechanisms of blood pressure control in states of catecholamine excess, we infused norepinephrine for 28 days using subcutaneously implanted osmotic pumps in dogs previously instrumented for monitoring left ventricular dynamics and cardiac output. Plasma norepinephrine rose from 238 +/- 27 to 4346 +/- 952 pg/ml at 21 days, while epinephrine and dopamine levels did not change. Heart rate fell from 85 +/- 4 to 63 +/- 6 beats/min, while arterial pressure was unchanged from baseline.