Abstract
The purpose of this study was to investigate the efficacy, effective dose, administration frequency and antianginal effect of a new antianginal agent, nipradilol, in 12 patients with stable effort angina. A single blind design was employed; the test consisted of an observation period (1 week) and a treatment period (1-2 weeks). Twenty four hour Holter monitoring was performed on the penultimate day of each period. Nipradilol was administered twice a day at a daily dose of 3-12mg (mean 7.9±3.3mg). The mean frequency of ST-segment depression was 7.1±6.7 times per day at baseline and 3.1±2.7 after drug administration, showing a significant reduction (p<0.05). The suppression of ST-segment depression and decrease in heart rate due to this drug persisted for 12 hours following administration. The plasma drug concentration at a daily dose of 12mg peaked at 9.5±2.4ng/ml 1 hour after administration and the 12 hour value was 2.3±1.2ng/ml. No side effects were observed. Therefore, it seems that, when administered twice a day (total daily dose 6mg) this drug is effective in effort angina and that the antianginal effect is mainly attributable to β-adrenoceptor blockade.
