Calcium antagonists for the treatment of various anginal syndromes

The three calcium antagonists-verapamil, nifedipine, and diltiazem-have proved to be effective in patients with a variety of anginal syndromes. All three agents have been shown to be highly efficacious (either alone or in combination with long-acting nitrate preparations) in patients with Prinzmetal's variant angina, which is due to coronary arterial spasm. Each of these agents has proved to be superior to placebo in patients with angina of effort, and verapamil has been shown to be more effective than β-adrenergic blockade in these individuals. Furthermore, in patients with especially severe angina of effort, both a propranolol-verapamil and a propranolol- nifedipine combination have proved to be more effective than any of these agents alone. Finally, all three calcium antagonists have been shown to be highly effective in patients hospitalized with unstable angina at rest. In short, verapamil, nifedipine, and diltiazem-administered alone or in conjunction with nitrates and even with β-adrenergic blocking agents-are becoming increasingly popular in the treatment of several anginal syndromes.