Comparison of the antianginal efficacy of four calcium antagonists and propranolol in stable angina pectoris

Abstract

The antianginal effects of propranolol 160 mg/day, diltiazem 240 mg/day, nicardipine 80 mg/day, nifedipine 40 to 80 mg/day and verapamil 320 mg/day were compared in 12 patients with chronic stable angina pectoris using a symptom-limited exercise test. Compared to placebo propranolol and calcium antagonists similarly reduced (p less than 0.001) the frequency of antianginal attacks and nitroglycerin consumption, and increased exercise tolerance and time to greater than or equal to 1 mm S-T segment depression. After propranolol the pressure-rate product at submaximal and maximal exercise was significantly decreased. The calcium antagonists produced a significant reduction in the submaximal pressure-rate product, but no significant change in the peak pressure-rate product. Maximum ST depression was significantly lower after propranolol and was unchanged after the calcium antagonists. None of the drugs caused significant adverse effects. The results indicate that in patients with stable effort angina pectoris, diltiazem, nicardipine, nifedipine and verapamil were as effective as propranolol in improving exercise tolerance and time to ischaemia, and they did not alter the peak pressure-rate product. Different antianginal mechanisms may be operative for the various calcium antagonists.