Randomized, placebo-controlled trial of the angiotensin-converting enzyme inhibitor, ramipril, in patients with coronary or other occlusive arterial disease

OBJECTIVES The primary objective of this study was to investigate the effec ts of the angiotensin-converting enzyme (ACE) inhibitor, ramipril, on carot id atherosclerosis in patients with coronary, cerebrovascular or peripheral vascular disease. BACKGROUND Angiotensin-converting enzyme inhibitors have been shown to redu ce the risk of coronary events in various patient groups and to prevent the development of atherosclerosis in animal models. It has been hypothesized that the clinical benefits of ACE inhibitors may, therefore, be mediated by effects on atherosclerosis. METHODS Six hundred seventeen patients were randomized in equal proportions to ramipril (5-10 mg daily) or placebo. At baseline, two years and four ye ars, carotid atherosclerosis was assessed by B-mode ultrasound, and left ve ntricular mass was assessed by Ill-mode echocardiography. RESULTS Blood pressure (BP) was reduced by a mean of 6 mm Hg systolic and 4 mm Hg diastolic in the ramipril group compared with the placebo group (p < 0.001). There was no difference between groups in the changes in common ca rotid artery wall thickness (p 0.58) or in carotid plaque (p = 0.93). Left ventricular mass index decreased by 3.8 g/m(2) (4%) in the ramipril group c ompared with the placebo group (2p = 0.04). CONCLUSIONS The results provide no support for the hypothesis that reduced atherosclerosis is responsible for the beneficial effects of ACE inhibitors on major coronary events. It is more likely that the benefits are due to l ower BP, reduced left ventricular mass or other factors such as reversal of endothelial dysfunction. (C) 2000 by the American College of Cardiology.