Delapril versus enalapril in patients with congestive heart failure

Abstract

This 12-month, multicenter, randomized, parallel-group study compared the effects of delapril with enalapril in 179 patients with congestive heart failure, New York Heart Association (NYHA) classes II and III. The initial doses of delapril (7.5 mg twice daily [BID]) and enalapril (2.5 mg BID) could be doubled every other week, to a maximum of 30 mg BID and 10 mg BID, respectively. Efficacy was assessed based on the changes in NYHA class, echocardiographic variables, cardiothoracic ratio, left ventricular end-diastolic volume, left ventricular end-systolic volume, left ventricular systolic wall stress, ejection fraction results of the exercise test, and patient's opinion of clinical status using a 4-point scale. Safety was assessed by monitoring the adverse events, laboratory tests, blood pressure, and electrocardiography. A significant decrease in left ventricular end-systolic volume was observed in the delapril group after 3 ( P < 0.01), 6 ( P < 0.01), and 12 ( P < 0.05) months; no significant changes were seen in the enalapril group in this period. Both treatments significantly reduced wall stress and improved ejection fraction at 3 (delapril, P < 0.01; enalapril, P < 0.05), 6 ( P < 0.01 for both groups), and 12 (delapril, P < 0.01; enalapril, P < 0.05) months, and significantly improved ejection fraction ( P < 0.01). None of the between-group differences were significant. Both treatments produced a significant improvement compared with baseline in the duration of exercise, workload, and work performed at 3 and 12 months. There was a significant difference between treatments in workload at 3 months ( P < 0.05) in favor of delapril. Heart rate was significantly reduced at day 30 ( P < 0.01), day 45 ( P < 0.05), and month 6 ( P < 0.05) only in the delapril group. The frequency and type of adverse events were similar in the 2 groups. One-year mortality was 5.7% in the delapril group and 6.6% in the enalapril group. These results suggest that treatment with delapril, an angiotensin-converting enzyme (ACE) inhibitor with affinity and selectivity for the C-site of the left ventricle and coronary arteries, may have some modest benefits when compared with a nonselective ACE inhibitor such as enalapril. However, more study is needed in larger patient populations.