[The efficacy of proxodolol, a new beta-adrenoblockader with alpha-adrenoblockader properties, in its single use in patients with stable stenocardia of effort].

The paper presents the results of the first phase of clinical trials of prodoxolol, a beta-adrenoblocker having alpha-adrenoblocking activity in a ratio of 100:1, in patients with coronary heart disease concurrent with stable exercise-induced angina pectoris. The tolerance of single proxodolol doses (10 mg in 4 patients, 20 mg in 2 and 40 mg in 2) was studied. In all cases, proxodolol reduced resting heart rate by 6-18 beats/min, which lasted for 5 hours or more. Four patients had a proxodolol-induced 20 mm Hg or more decrease in systolic blood pressure lasting for 5 hours. In 10 patients, the antianginal and anti-ischemic effects of proxodolol were evaluated by pharmaco-dynamic studies consisting in threshold treadmill exercise tests before and 30 min, 2 and 6 hours after single placebo (in 10 patients) and proxodolol (40 and 80 mg in 3 and 7 patients, respectively) administration. In addition, 7 patients underwent pharmacodynamic studies with propranolol, 80 mg. The efficacy was judged from the increased exercise duration before an anginal episode (antianginal effect) and from the decreased ST segment depression during the identical exercise (anti-ischemic effect). The antianginal effect of proxodolol began 30 min later, reaching its peak 2 hours later and retained 6 hours later. During all study periods it was more marked than that of propranolol. The anti-ischemic effect of proxodolol was similar to the antianginal effects and it did not correlated with its chronotropic one. Proxodolol was well tolerated with patients. Thus, proxodolol in single doses of 40 and 80 mg produced antianginal and anti-ischemic effects and its action was similar to that of propranolol.(ABSTRACT TRUNCATED AT 250 WORDS)