[Effects of nipradilol on the patients of angina pectoris: results from the study of the exercise electrocardiography using HR-ST loop method].

This study was performed to confirm the usefulness of 12 mg nipradilol, a beta-blocker with a vasodilator action similar to that of nitrate-type drugs, in the treatment of effort angina pectoris. It also discusses the mechanism of the action of this drug when using the exercise test heart rate-ST displacement analysis. The symptom threshold multistage graded exercise test was performed using nine patients with chronic stabilized effort angina pectoris after an observation period and an 8-week administration period and HR-ST analysis was performed simultaneously. The number of anginal attacks significantly decreased from the 2nd week, and the heart rate at rest decreased significantly in the prone position although blood pressure did not change. The maximum oxygen intake increased markedly from 13.7 +/- 1.1 ml/kg/min to 19.3 +/- 2.5 ml/kg/min, and the maximum ST decrease improved significantly from 1.72 +/- 0.45 mm to 1.17 +/- 0.19mm. In HR-ST analysis, delta ST/delta HR and delta ST/delta DP tended to improve slightly. Since monotherapy with a beta-blocker causes significant increase in delta ST/delta HR and delta ST/delta DP, it was assumed that a vasodilator action in addition to a beta-blocker action is involved in the improvement of maximum ST decrease brought about by nipradilol.