[Comparative anti-ischemic activity of atenolol and diltiazem. Crossed single-blind randomized study using a...

The anti-ischaemic activities of atenolol (200 mg) and diltiazem (240 mg) were compared in 23 patients undergoing retraining 4 weeks after a limited postero-inferior or anterior primary myocardial infarction. The patients, who had signs of residual ischaemia during stress with or without angina, were subjected to 3 exercise tests on a bicycle ergometer; a computer was used to analyze the results (Case-Marquette). The first test was performed under placebo, the second after randomized treatment with one of the two drugs and the third test after taking the other drug. The parameters evaluated were: total duration of the test, time of occurrence of a 1 mm ST-segment depression, maximal work load and total work performed, heart rate, systolic arterial pressure, heart rate X systolic arterial pressure product at rest and at submaximal and maximal stress, and ST depression at submaximal and maximal stress. The results showed that exertion was improved to the same degree by the two drugs, but atenolol had greater anti-ischaemic activity than diltiazem.