A potassium channel opener as monotherapy in chronic stable angina pectoris: comparison with placebo.

The vasodilating agent nicorandil produces marked coronary artery dilatation by a number of mechanisms including an increase in cyclic guanosine monophosphate, an effect which is common to all organic nitrates, and a novel potassium channel opening effect. In four double-blind, placebo-controlled trials, nicorandil has been shown to produce beneficial haemodynamic effects in patients with stable angina pectoris without significant deleterious effects on pulse rate, the cardiac conducting system, myocardial contractility or myocardial oxygen consumption. Significant improvements in exercise time to onset of angina, exercise time to cardiac ischaemia and total attainable workload have been demonstrated. These effects have been shown to persist for 12 h, allowing it to be used on a twice daily basis. It appears relatively free of important side effects other than a dose-dependent headache, which necessitates discontinuation of treatment in a minority of patients.