Angiotensin-converting enzyme inhibitors in adults with cyanotic congenital heart disease

Renin-angiotensin-aldosterone inhibition improves right ventricular function: a meta-analysis

The benefits of inhibiting the renin-angiotensin-aldosterone system (RAAS) are well established for left ventricular dysfunction, but remain unknown for right ventricular (RV) dysfunction. The aim of the current meta-analysis is to investigate the role of RAAS inhibition on RV function in those with or at risk of RV dysfunction. Medline, PubMed, EMBASE and Cochrane Libraries were systematically searched and 12 studies were included for statistical synthesis, comprising 265 RAAS inhibition treatment patients and 265 placebo control patients. The treatment arm showed a trend towards increased RV ejection fraction (weighted mean difference (WMD)=0.95, 95% CI -0.12 to 2.02, p=0.08) compared with the control arm. Subgroup analysis demonstrated a trend towards improvement in RV ejection fraction in patients receiving angiotensin receptor blockers compared with control (WMD=1.11, 95% CI -0.02 to 2.26, p=0.06), but not in the respective comparison for ACE inhibitors (WMD=0.07, 95% CI -2.74 to 2.87, p>0.05). No differences were shown between the two groups with regard to maximal oxygen consumption, RV end-systolic volume, RV end-diastolic volume, duration of cardiopulmonary exercise testing, and resting and maximal heart rate. Mild adverse drug reactions were common but evenly distributed between the treatment and control groups. The current meta-analysis highlights that there may be a role for RAAS inhibition, particularly treatment with angiotensin receptor blockers, in those with or at risk of RV dysfunction. However, further confirmation will be required by larger prospective trials.

The renin-angiotensin-aldosterone-system and right heart failure in congenital heart disease

Adults with congenital heart disease represent a rapidly growing patient group. Dysfunction of the right ventricle is often present, and right heart failure constitutes the main cause of death. Heart failure therapies used in acquired left heart failure are often initiated in adults with right heart failure due to congenital heart disease, but the right ventricle differs substantially from the left ventricle, and the clinical evidence for this treatment strategy is lacking.

In this review, we identified existing clinical studies evaluating the effects of ACE inhibitors, angiotensin II receptor blockers and aldosterone antagonists in adults with congenital heart disease by a systematic literature search. From 13 identified studies no clear evidence of beneficial effects was found, but the design of the studies limits the validity of the results. The studies in general include low numbers of patients, have short follow-up periods and evaluate surrogate endpoints instead of hard clinical endpoints. Specific evaluation of symptomatic patients with a systemic right ventricle indicates that these patients may benefit from RAAS inhibitory treatments, but this requires further investigation.

To conclude, existing studies do not support the use of RAAS inhibitory treatments in right heart failure due to congenital heart disease but contain important limitations. Hence, there is a need for new well-designed trials including higher numbers of patients and validated endpoints to optimize and guide future treatment of this patient group.

The exceptional and far-flung manifestations of heart failure in Eisenmenger syndrome

Dramatic advances in the diagnosis and treatment of congenital heart disease (CHD), the most common inborn defect, has resulted in a growing population of adults with CHD. Eisenmenger syndrome (ES) represents the extreme form of pulmonary arterial hypertension associated with CHD, characterized by markedly increased pulmonary vascular resistance with consequently reversed or bidirectional shunting. While ES is a direct consequence of a heart defect, it is a fundamentally multisystem syndrome with wide-ranging clinical manifestations. The introduction of targeted pulmonary hypertension therapies aimed has subtly shifted clinical focus from preventing iatrogenic and other adverse events toward cautious therapeutic activism.

Eisenmenger syndrome: medical prevention and management strategies

The original definition of Eisenmenger syndrome refers to an unrestrictive post-tricuspid valve congenital systemic-to-pulmonary shunt. When the pulmonary arterial systolic pressure becomes equal to the systemic arterial systolic pressure, the direction of the shunt becomes pulmonary-to-systemic. The latter leads to progressive cyanosis, and exercise intolerance is initially proportional to the degree of hypoxaemia. Later, congestive heart failure may occur . The management principle is to avoid any factors that destabilise this delicately balanced physiology. Until recently, this could only be achieved by symptomatic therapy; however, when patients are severely incapacitated, transplantation is needed. At present, new drugs, which are more selective pulmonary vasodilators, are available to interfere with the ongoing disease process to improve functional capacity and delay the decision for transplantation.

Applying standard therapies to new targets: the use of ACE inhibitors and B-blockers for heart failure in adults with congenital heart disease

Increasingly, patients and clinicians are being confronted with congestive heart failure (CHF) as a late complication of congenital heart disease. However, medical management of heart failure in this patient group represents a challenge because of complex hemodynamics and a lack of evidence from large randomized controlled trials to guide therapy. This article will review the evidence of the use angiotensin converting enzyme inhibitors (ACEIs) and beta-blockers (BBs) in left heart failure, discuss the mechanisms of heart failure as they pertain to congenital heart disease and review the limited literature of the use of neurohormonal antagonists in congenital heart disease. Some recommendations for use of angiotensin converting enzyme inhibitors and beta-blockers in heart failure due various congenital heart lesions are offered. Well-designed clinical trials are urgently needed to extend the impressive reductions in morbidity and mortality achieved with neurohormonal blockade in left ventricular (LV) heart failure to adults with congenital heart disease.

Assessment of intracardiac anomalies in two adults with Ivemark's syndrome

Ivemark's syndrome consists of intracardiac anomalies, abnormal lobation of the lungs, and abdominal heterotaxy. A frequent intracardiac anomaly seen in Ivemark's syndrome is a common atrium, which is associated with left-to-right shunting. The increased blood flow and resistance within the pulmonary vasculature creates pulmonary hypertension and eventual reversal of the shunt physiology. In the absence of additional cyanotic malformations, survival into adulthood without prior surgical septation of the common atrium depends on the extent of pulmonary hypertension and intracardiac right-to-left shunting. We present two patients with a common atrium in the setting of Ivemark's syndrome who survived into adulthood without prior operation. Two-dimensional echocardiography assessed their intracardiac structures. One patient had right atrial isomerism manifested by asplenia and a common atrium, into which the hepatic veins drained directly, and the other patient had left atrial isomerism manifested by polysplenia, a common atrium, and a ventricular septal defect with a single atrioventricular valve. Neither patient had additional cyanotic malformations, including obstruction to pulmonary venous return, transposition of the great vessels, or pulmonic valve stenosis. The 2-dimensional echocardiogram guides the clinician to refer patients for surgical septation of the common atrium before the right-to-left shunt physiology predominates. The medical and surgical treatment of these patients is discussed.

Angiotensin-converting enzyme inhibitor therapy for ventricular dysfunction in infants, children and adolescents: a review

Angiotensin-converting enzyme (ACE) inhibitors have become an important part of the pharmacologic armamentarium in the battle against treatment of ventricular dysfunction. There have been a number of large controlled, randomized trials in adults with both asymptomatic and symptomatic ventricular dysfunction, which confirm the safety and efficacy of this category of drugs for the treatment of this potentially lethal condition. ACE inhibitors may be used to treat infants, children and adolescents with asymptomatic and symptomatic ventricular dysfunction as well. The data supporting their use in children is less complete than that concerning the treatment of adults. We review here the various causes of ventricular dysfunction and congestive heart failure (CHF) in infants, children, and adolescents; the data available regarding treatment of these conditions with ACE inhibitors, and the safety and efficacy of these drugs for the various conditions. The pharmacokinetics and proposed mechanisms of action of ACE inhibitors in children are reviewed, as are speculated long-term results of ACE inhibitor use in cohorts of growing children. Recommendations are made for future studies.

Eisenmenger syndrome in adults: ventricular septal defect, truncus arteriosus, univentricular heart

OBJECTIVES

Morbidity and mortality patterns were characterized in adults with the Eisenmenger syndrome when two ventricles with a ventricular septal defect (VSD) joined two great arteries or one great artery, or when one ventricle joined two great arteries.

BACKGROUND

Although afterload in these disorders differs, clinical differences have not been defined.

METHODS

Seventy-seven patients were studied. Group A comprised 47 patients with VSD, aged 23 to 69 years (mean 39.5+/-10.2), follow-up 5 to 18 years (mean 7.2+/-4.9); group B, 14 patients with truncus arteriosus, aged 27 to 50 years (mean 33.7+/-7.3), follow-up 6 to 18 years (mean 7.7+/-5.1), and group C, 16 patients with univentricular heart, aged 18 to 44 years (mean 30.6+/-8.4), follow-up 5 to 15 years (mean 4.4+/-4.2). Echocardiography established the diagnoses and anatomic and hemodynamic features. Data were compiled on tachyarrhythmias, pregnancy, infective endocarditis, noncardiac surgery and the multisystem disorders of cyanotic adults.

RESULTS

Thirty-five percent of the patients died. Sixty-three percent of deaths were sudden, and resulted from intrapulmonary hemorrhage, rupture of either the pulmonary trunk, ascending aorta or a bronchial artery, or vasospastic cerebral infarction, or the cause was unestablished. There were no documented tachyarrhythmic sudden deaths.

CONCLUSIONS

Medical management of coexisting cardiac disease, multisystem systemic disorders, noncardiac surgery and pregnancy has reduced morbidity. Increased longevity exposed patients to proximal pulmonary arterial aneurysms, thromboses and calcification; to truncal valve stenosis and regurgitation; to semilunar and atrioventricular valve regurgitation, and to major risks of nontachyarrhythmic sudden death.