The effect of pindolol on the two years mortality after complicated myocardial infarction

The effect of oral pindolol 15 mg daily was compared with placebo in 529 patients who had electrical and/or mechanical complications after an acute myocardial infarction. The study was multicentric (five in Sweden, two in Australia) and patients were allocated in a stratified manner to placebo (266 patients) or pindolol (263 patients). Treatment was started 1--21 days after infarction and patients were followed for 2 years. Forty-seven patients (17.7%) in the placebo group and 45 patients (17.1%) in the pindolol group died. In patients who commenced therapy later than 5 days after myocardial infarction mortality was 18% lower in the pindolol group and there was an even greater difference in patients who commenced therapy after 12 days. Patients who were on digitalis therapy had a lower mortality if treated with pindolol. The apparent improvement in prognosis in patients treated in Sweden compared to Australia may have been due to later entry of patients. This study suggests that improvement in prognosis when beta blocking drugs are given after myocardial infarction may only apply to certain groups of patients. No benefit is gained by commencing an oral beta blocking drug immediately and such therapy need not be started before 1 week or more after the myocardial infarct.