Enalapril is an effective angiotensin-converting enzyme (ACE) inhibitor which produces salutary, beneficial haemodynamic effects in patients with congestive heart failure. Enalapril also produces beneficial neurohumoral changes, as well as improving abnormal coronary haemodynamics and myocardial energetics that are frequently encountered in these patients. Administration of enalapril once or twice daily appears to be quite effective during maintenance therapy in patients with chronic congestive heart failure.