Beta-blockers in the secondary prevention of myocardial infarction: a review of clinical trials of 12 months or more duration.

Data from six placebo-controlled prevention trials studying the effect of beta-blocker therapy after myocardial infarction are reviewed for comparison. The beta-blockers chosen for this review were practolol, oxprenolol, timolol, sotalol and propranolol. All studies had a duration of at least 12 months and treatment was started not earlier than 4 days and not later than 4 months after the onset of infarction. The patient selection did not reveal marked differences concerning the pre-infarct history whereas risk factors at entry varied considerably between the trials. In spite of these differences, all of the six studies showed a reduction in overall mortality and in the rate of non-fatal reinfarctions of the treated group as compared with placebo. Based on these results, the practical implications are discussed in an attempt to draw some general guidelines concerning the management of therapy. Finally, it appears that beta-blocking activity is the common factor for improving the long-term survival of post-infarction patients.