Chronic effects of nicorandil on exercise tolerance in patients with stable effort angina pectoris

To examine the chronic effects of nicorandil, a new coronary vasodilator, on exercise tolerance, we gave this drug for ten days at 15 mg/day orally in three divided doses to 10 patients with stable effort angina. An increase in exercise capacity by more than 1 stage of modified Bruce's protocol was observed in 6 of 10 patients on the 5th and 10th day after the administration. The exercise duration was significantly prolonged from 294 +/- 86 sec (mean +/- SD) before the administration to 363 +/- 106 sec and 405 +/- 139 sec on the 5th and 10th day after the administration, respectively. With nicorandil administration, the time to 0.1 mV of ST-segment depression was also significantly delayed from 3.1 +/- 1.9 minutes to 4.5 +/- 2.6 minutes on the 10th day. On the other hand, systolic blood pressure, heart rate and pressure rate product did not demonstrate any significant change before and after the administration. These results indicate that oral nicorandil of 5 mg 3 times a day can chronically increase exercise tolerance without decreasing myocardial oxygen consumption in patients with stable effort angina.