[Calcium antagonists and coronary heart disease. An overview]

Calcium antagonists (Ca-antagonists) have been used for 2 decades in the treatment of coronary heart disease. Their use has initially been promoted with variant angina, but soon has expanded to all forms of coronary heart disease, entailing both stable and instable angina. Based on promising experimental findings, these drugs have also been given in myocardial infarction, however, with disappointing results. The same was true for secondary prevention. The basic principle underlying Ca-antagonistic therapy of ischaemic heart disease is the improvement of myocardial oxygen balance. On the one hand, Ca-antagonists (in particular verapamil and diltiazem) reduce myocardial oxygen demand via negative inotropic and chronotropic action--on the other hand, the afterload is reduced by peripheral vasodilation. In addition, coronary dilation improves oxygen delivery, especially during exercise. Ca-antagonists inhibit transsarcolemmal Ca-influx, thus preventing deleterious myocardial Ca-overload as seen during ischaemia and atherosclerosis. Indeed, recent human studies have proven a preventive effect of Ca-blockers against atherosclerosis.