Drug Therapy in Angina Pectoris

DRUGS which relax spasm of the smooth muscles of the coronary vessels are used in the symptomatic treatment and prophylaxis of angina pectoris. Their use is based upon the assumption that angina is the result of myocardial ischemia and hypoxia caused by localized vascular constriction. Some investigators believe that these drugs act, at least in part, by lessening the work of the heart or by reducing the oxygen requirement of the myocardium. The vasodilator drugs used as antianginal agents are of two types: (1) those which act rapidly torelieveparoxysmal attacks of angina pectoris, and (2) drugs with a slower onset and longer duration of action which are intended topreventattacks of acute pain. Glyceryl trinitrate (nitroglycerin) is the prototype of the agents used to treat acute attacks of angina pectoris. Taken sublingually at the onset of chest pain, it usually provides complete relief in one to three