The Beta-blocker Heart Attack Trial.

The preventive effect of long-term beta-blocker therapy in patients who have survived the acute phase of myocardial infarction has been examined in several controlled clinical trials. The largest, the Beta-Blocker Heart Attack Trial, has convincingly demonstrated that propranolol in a daily dose of 180 to 240 mg given to patients without absolute or relative contraindications to the drug, prolongs life while producing moderate side effects. The predominant benefit appears to be in the first 12-18 months. The prime candidates for treatment seem to be patients at high risk, i.e. with complicated infarctions or complex arrhythmias. The likely mechanisms of action are anti-arrhythmic and anti-ischemic. Beta-2 blockade may be a contributing factor.