Recent developments in the use of calcium antagonists in myocardial protection

For more than two decades calcium antagonists (CEBs) have been widely used for the treatment of myocardial ischaemia (angina pectoris). Amongst the classes of CEBs, the 1,4-dihydropyridines (DHPs), like nifedipine, have been used for this indication because of their haemodynamic and electrophysiological properties. The ability of nifedipine to reduce afterload and to induce coronary vasodilation, as well as to increase collateral blood supply, has supported its extensive use in the treatment of angina pectoris. However, its short duration of action also provokes reflex tachycardia, which often limits its beneficial effect and may actually precipitate pain. The newer DHPs, such as amlodipine and lacidipine, are endowed with slow onset and long duration of vasodilatory activity; they are able to reduce coronary resistance with little or no effect on heart rate. The more lipophilic DHP, lacidipine, shows also a pronounced vascular protection, on both smooth muscle and endothelium, and is able to reduce the formation of atheroma plaque in animal models at therapeutic doses. This protective activity might be explained in terms of both the effective CEB activity of lacidipine together with antioxidant properties that this DHP has shown.