Calcium plays a critical role as a modulator aand initiator of many cellular functions. Chief among these are striated and smooth muscle contraction, electrical activation of various excitable cells, neurotransmitter release, platelet aggregation, and chemotaxis, as well as endocrine and exocrine gland secretion. Although calcium channel blocking agents influence each of these physiologic processes, their major clinical impact has been on the treatment of cardiovascular disorders. In this article, we propose (1) to discuss what we have learned recently about calcium channels in the heart and vessels and their response to calcium channel blockers and, (2) to review the clinical results obtained with these new drugs in the treatment of cardiac arrhythmias, myocardial ischemic syndromes and systemic hypertension.
