[The use of labetalol and propranolol in patients who have had a myocardial infarct].

Paired bicycle ergometry [correction of veloergometric] testing was carried out in 94 patients with a history of myocardial infarction before and after single intakes of 40 mg of obsidan and 200 mg of labetalol. The effect of these agents on the increase of tolerance to physical load was evaluated. It was found that obsidan and labetalol increased the tolerance of these patients to physical loads. The positive effect was realized due to negative chronotropic effect of obsidan and reduction of the systemic arterial pressure under the effect of labetalol.