EFFECTS OF ONCE-DAILY BENAZEPRIL THERAPY ON EXERCISE TOLERANCE AND MANIFESTATIONS OF CHRONIC CONGESTIVE-HEART-FAILURE

The effects of the long-acting angiotensin-converting enzyme inhibitor benazepril hydrochloride on exercise tolerance and signs and symptoms of congestive heart failure (CHF) were evaluated in a double-blind, multicenter, placebo-controlled clinical trial. Patients with chronic New York Heart Association class 11 to IV symptoms of CHF and an ejection fraction by radionuclide scanning of less-than-or-equal-to 35% were randomized in a 2:1 ratio to treatment with ascending doses of oral benazepril (n = 114) or placebo (n = 58) once daily, while continuing to receive background therapy with digoxin and diuretics. After randomization, patients were evaluated clinically every 2 weeks during a 12-week, double-blind treatment period. Maximal exercise tolerance was measured before and at specified time points after randomization by graded treadmill exercise testing. At week 12, mean exercise time increased 95 +/- 12 (SEM) seconds in the group receiving benazepril, whereas the increase was 37 +/- 18 seconds in the group receiving placebo (p <0.01 for the difference between the groups). There was also greater improvement in overall clinical status and in the signs and symptoms of CHF in benazepril-treated patients than in control subjects. There were 3 deaths in placebo-treated patients and none in benazepril-treated patients (p <0.05); the overall incidence of adverse effects was identical in the 2 groups. Benazepril is a well-tolerated angiotensin-converting enzyme inhibitor that provides clinically important improvement in exercise tolerance and in signs and symptoms when given once daily to patients with CHF receiving background therapy with digoxin and a diuretic.