Low-dose enalapril in severe chronic heart failure

Abstract

In a 3-month prospective, single-blind, controlled trial, 38 patients in New York Heart Association functional class III-IV were assigned to group E (n = 19): enalapril 5 mg/day in addition to the previous therapy with digitalis and diuretics, or group C (n = 19): continuation of the previous therapy. In group E, 79% of the patients improved by at least one NYHA functional class after 3 months. In group C, the functional class did not change and four patients died. The echocardiographically determined end-diastolic diameter of the left ventricle decreased in group E from 72 +/- 8 mm to 63 +/- 6 mm (p less than 0.001), and the scintigraphically determined ejection fraction of the left ventricle increased from 33 +/- 18% to 40 +/- 19% (p less than 0.002). In contrast, no significant change was found in group C. Plasma-renin activity increased in group E from 8.2 +/- 1.8 ng/ml h to 29.7 +/- 14 ng/ml h (p less than 0.001), and plasma aldosterone decreased from 47.7 +/- 7.6 ng/dl to 19.9 +/- 4.8 ng/dl (p less than 0.01). In group C no significant change occurred. Comparing the actual changes (deltas) of the NYHA functional class (p less than 0.02), end-diastolic diameter and ejection fraction of the left ventricle, plasma-renin activity, and plasma aldosterone (p less than 0.0001), a significant difference between the two groups was found. Thus, low-dose enalapril resulted in a significant improvement of the NYHA functional class in patients with severe chronic heart failure, accompanied by an improvement in left ventricular function and a decrease in secondary aldosteronism.

Current Controversies with ACE Inhibitor Treatment in Heart Failure

“…Only indirect evidence from small studies can be obtained using combined end points or symptoms and exercise tolerance. Brilla et al [8], Sharpe et al [9] and Franciosa et al [10] observed an improvement in symptoms and exercise performance in heart failure patients on low-dose ACE inhibitors. Klcber et al [11] found a reduction of combined mortality and morbidity in heart failure patients on low-dose ACE inhib itor.…”

Choice of ACE inhibitor for congestive heart failure

“…Regarding the enalapril dose, as little as 5 mg daily has been used in severe heart failure with apparent hemodynamic benefit [7]. In the latter study, half of 38 patients in heart failure functional category III or IV were assigned to additional therapy with enalapril 5 mg daily or to a continuation of previous therapy.…”