Abstract

Vasodilators are commonly prescribed for the treatment of angina pectoris. Their effects are determined by their site of action in the cardiovascular system. Drugs which are relatively selective venodilators, such as the organic nitrates, relieve (or prevent) angina by lowering ventricular filling pressure, so reducing ventricular size and hence myocardial wall tension; this reduces myocardial work and hence oxygen demand. The fall in ventricular diastolic pressure may also help by permitting an increase in coronary perfusion, since this depends on the difference between aortic and ventricular diastolic pressures.