Verapamil therapy in variant angina pectoris refractory to nitrates.

Conventional therapy including nitrates, beta blockers, and surgical bypass has proved to be generally unsatisfactory in patients with variant angina of suspected vasospastic etiology. Recent evidence regarding the role of calcium in the pathogenesis of vascular smooth muscle spasm prompted an open study of the clinical effects of verapamil in seven patients with recurrent rest angina refractory to nitrates. The patients studied met strict clinical ECG and angiographic criteria for vasospastic angina. All patients had rapid (within 24 hours) and complete (without recurrence of symptoms) chronic response to oral verapamil therapy. The pharmacology of verapamil relating to the pathogenesis of vasospastic angina is delineated and guidelines for the clinical application of the agent are presented.