Effect of enalapril on infants and children with congestive heart failure

Summary The effect of enalapril, an inhibitor of angiotensin converting enzyme, was studied in 35 infants and children with congestive heart failure associated either with residual mitral or aortic regurgitation following intracardiac repair (24 patients) or with dilated cardiomyopathy (11 patients). Enalapril, at an average dose of 0.24 ±0.10 mg/kg, reduced the concentration of angiotensin II in the serum from 115 ± 67 pg/ml to 60 + 30 pg/ml and increased plasma renin activity from 25 + 24 ng/ml/hr to 45 ± 37 ng/ml/hr. There was a significant decrease in hepatomegaly, cardiothoracic ratio, heart rate and blood pressure in both groups of patients. Left ventricular end-diastolic dimension as evaluated by cross-sectional echocardiography, also decreased, whereas fractional shortening and systolic time intervals improved in both groups of patients. Adverse effects were noted in only one infant with postoperative mitral regurgitation who developed renal failure with oliguria, increase of blood urea nitrogen and serum creatinine. Renal function improved dramatically after discontinuation of enalapril. Hyperkalemia (>5mEq/ 1) was observed in four patients, three of whom were receiving spironolactone. Our results showed that enalapril is effective in improving hemodynamics in the relatively short-term treatment of infants and children with congestive heart failure due to postoperative volume overload or dilated cardiomyopathy. These conditions are poorly controlled with conventional medical therapy.