Verapamil versus propranolol for angina at rest

We previously showed that verapamil is highly effective in the treatment of patients with angina at rest, in whom coronary vasospasm likely represents the primary underlying pathophysiologic mechanism. Beta-adrenergic blocking drugs, on the other hand, do not exert any vasodilating effect on large coronary arteries, and hence do not represent a rational therapeutic approach to the treatment of patients with this syndrome.The present report reviews the results of three clinical trials comparing the effectiveness of verapamil and propranolol in patients with angina at rest. In 17 patients enrolled in a randomized triplecrossover study, verapamil was superior to propranolol in preventing ergonovine-induced coronary artery spasm (p < 0.001). In 18 patients with rest angina evaluated in a double-blind crossover study, both verapamil and propranolol reduced the number of episodes of angina at rest (from 3.0/day to 1.7/day with propranolol, p < 0.05, and to 0.2/day with verapamil, p < 0.001); the degree of improvement with verapamil was superior to that seen with propranolol (p < 0.005). In 10 patients with rest angina evaluated in a single-blind multiple crossover trial which assessed symptomatic and asymptomatic ischemia, the number of ischemic events was reduced significantly only by verapamil (5 ± 1 episodes/48 hours) but not by placebo or propranolol (25 ± 3 and 23 ± 3 episodes/48 hours, respectively).These studies confirm the effectiveness of verapamil in the management of patients with angina at rest; in contrast, the effectiveness of propranolol in this syndrome appears comparable to that of placebo.