Current Status of Calcium Channel Blockers After Myocardial Infarction

Abstract

Three calcium channel blocking agents—diltiazem, nifedipine, and verapamil—are approved by the Food and Drug Administration (FDA) for use in the United States. These agents are effective in the treatment of vasospastic angina, exertional and decubitus angina associated with obstructive atherosclerotic disease, and so called mixed angina with both vasospastic and obstructive components. All three of these agents reduce the frequency of angina pectoris, diminish the utilization of nitroglycerin, and increase the duration of time on treadmill testing before the development of angina in patients with coronary heart disease. Because calcium channel blockers have antianginal efficacy similar to the more established beta blocker class of drugs, the calcium antagonist drugs are being used extensively in acute coronary disease without prior evidence of safety and efficacy from appropriate clinical trials. Furthermore, each of the three calcium channel blocking agents has a different mechanism and spectrum of action, and the findings from one agent can not be extrapolated to the other agents in this class as safely as was done among the beta blockers. With this background, I will explore the current state of our knowledge and experience regarding the appropriate use of calcium blockers after myocardial infarction.