[Calcium antagonists in the treatment of heart diseases].

The beneficial action of calcium antagonists in the therapy of different cardiac diseases is based on one fundamental effect, i.e. reduction of the transmembrane calcium conductivity of myocardial muscle fibers and vascular smooth musculature. The pharmacologic effects of calcium antagonists can be summarized as follows: 1. The myocardium shows a reduction in oxygen consumption due to the decrease in systolic wall stress and depression of myocardial metabolism. 2. Pacemaker activity and AV-node conduction are depressed, while ectopic pacemaker activities are effectively suppressed and reentry mechanisms are blocked. 3. The vascular smooth musculature shows a reduction of vascular tone and suppression of arterial spasms. The clinical use of calcium antagonists is based on the following four important therapeutic factors: 1. antianginal effect, 2. antiarrhythmic effect, 3. antihypertensive effect, 4. cardioprotective effect. Currently the calcium antagonists are used mainly in the treatment of supraventricular tachyarrhythmias and coronary vasospasms. New fields for calcium blockers may be therapy of hypertrophic cardiomyopathy and myocardial protection during acute myocardial ischemia.