SELECTION OF MEDICAL-TREATMENT IN STABLE ANGINA-PECTORIS - RESULTS OFTHE INTERNATIONAL MULTICENTER ANGINA EXERCISE (IMAGE) STUDY

Objectives. The present study was designed to investigate,which charac teristics of anginal symptoms or exercise test results could predict t he favorable anti-ischemic effect of the beta-adrenergic blocking agen t metoprolol and the calcium antagonist nifedipine in patients with st able angina pectoris. Background. The characteristics of anginal sympt oms and the results of exercise testing are considered of great import ance for selecting medical treatment in patients with chronic stable a ngina pectoris. However, little information is available on how this f irst evaluation may be used to select the best pharmacologic approach in individual patients. Methods. In this prospective multicenter study , 280 patients with stable angina pectoris were enrolled in 25 Europea n centers. After baseline evaluation, consisting of an exercise test a nd a questionnaire investigating patients' anginal symptoms, the patie nts were randomly allocated to double-blind treatment for 6 weeks with either metoprolol (Controlled Release, 200 mg once daily) or nifedipi ne (Retard, 20 mg twice daily) according to a parallel group design. A t the end of this period, exercise tests were repeated 1 to 4 h after drug intake. Results. Both metoprolol and nifedipine prolonged exercis e tolerance over baseline levels; the improvement was greater in the p atients receiving metoprolol (p < 0.05). Multivariate analysis reveale d that low exercise tolerance was the only variable associated with a more favorable effect within each treatment group. Metoprolol,vas more effective than nifedipine in patients with a lower exercise tolerance or with a higher rate-pressure product at rest and at ischemic thresh old. None of the characteristics of anginal symptoms or exercise test results predicted a greater efficacy of nifedipine over metoprolol. Co nclusions. The results of a baseline exercise test, but not the charac teristics of anginal symptoms, may offer useful information for select ing medical treatment in stable angina pectoris.