Background: Nicorandil is a hybrid-type anti-anginal drug that combines a K(ATP) channel opener and a nitric oxide donor. Recently the IONA study reported that nicorandil improves the prognosis of patients with stable angina pectoris.
Methods and results: To examine the effects of nicorandil on endogenous fibrinolysis, plasma concentrations of tissue-type plasminogen activator (t-PA) antigen, type-1 plasminogen activator inhibitor (PAI-1) antigen and PAI activity were measured in consecutive 11 patients (7 men and 4 women, mean age 63 years, ranges 41-84 years) with coronary artery disease. Nicorandil (15 mg/day) was administered orally to each patient for 2 weeks. Venous blood samples were obtained from each patient before and after the administration of the drug in the early morning before eating. There were no significant changes in the plasma concentrations of t-PA (12.4+/-1.9 to 9.8+/-1.5) or PAI-1 (26.3+/-3.9 to 21.5+/-4.9) antigens (ng/ml, mean +/- SEM) before and after nicorandil administration. On the other hand, the plasma activity of PAI (IU/ml, mean +/- SEM) decreased significantly after the treatment (12.9+/-3.2 to 5.6+/-1.9, p=0.039).
Conclusions: It is well known that PAI activity determines the whole fibrinolytic capacity and oral administration of nicorandil decreased PAI activity in patients with coronary artery disease. This finding suggests that nicorandil improves the fibrinolytic capacity and may reduce the risk of coronary thrombus formation in such patients.