Effects of a single oral administration of Epanolol on exercise tolerance in patients with stable effort angina pectoris.

A single oral dosage of 100, 200 or 300 mg Epanolol or placebo was administered in a randomized double-blind, cross-over fashion to 12 patients with stable effort angina. Symptom limited bicycle ergometer tests were performed before and 2 and 8 hours after each drug administration. Spontaneous diurnal and day to day differences in exercise tolerance and related analyzed variables were not present; 48 hours after drug intake a carry-over effect of the previous Epanolol administration could not be demonstrated. At each dose level of Epanolol, 2 hours after drug intake, heart rate and rate pressure product at peak exercise fell while exercise duration rose significantly. After 8 hours these effects were less marked. No significant differences between the 3 dose levels were found. In the pooled data of the 3 Epanolol doses, systolic blood pressure at peak exercise and maximal ischemic ST segment depression during exercise were also significantly reduced after 2 hours, while total performed external work rose. The percentage increase in heart rate during exercise after Epanolol administration was similar to the control tests at lower exercise levels but was less marked during the later stages of the test. Heart rate after Epanolol intake was percentage wise more reduced at higher exercise levels. Plasma levels of Epanolol were lower 8 hours after drug administration than after 2 hours. There was no correlation between plasma levels of Epanolol and the observed changes of any of the exercise variables 2 hours after drug intake.