Effects of enalapril in normotensive patients with stable effort angina: a double blind, placebo controlled study

To assess the anti-anginal and anti-ischaemic efficacy of the ACE-inhibitor enalapril in normotensive coronary patients, a double-blind, cross-over, placebo-controlled study was performed. Eight male patients, aged 45-68 years, with stable effort angina were given enalapril (10 mg) once a day or placebo for 7 days. Maximal exercise stress tests 10w/min in the upright position were performed at the end of each period. In comparison to placebo, enalapril increased significantly 1 mm of ST depression time and decreased significantly ST depression at maximal common work. Moreover, enalapril increased significantly the angina threshold and exercise duration. Three of the eight patients ended the exercise without pain. The rate-pressure product was not significantly modified at any time. Thus, the anti-ischaemic and anti-anginal activity may be due to an increase of coronary blood flow, rather than a reduction of MVO2 consumption.