Several large recent clinical trials have established with reasonable certainty that chronic beta blocker therapy after acute myocardial infarction reduces two-year mortality by approximately 30%.1,2 However, given the projected 10% mortality during this time period, 100 patients must be treated to potentially save three lives. Identification of subgroups most (or least) likely to benefit from beta blockade would therefore be helpful. In a recently completed detailed analysis of the deaths in the Beta Blocker Heart Attack Trial (BHAT), we could find no major difference between propranolol and placebo groups in mechanism of death, incidence and type of acute or prodromal signs and symptoms, location of death, activity preceding death, or the percentage of deaths that were sudden or instantaneous.3 Thus, the protective effect of propranolol after myocardial infarction may be multifactorial.
Despite the almost 4000 patients participating in the trial, the total number of deaths is relatively small
Peters RW. Beta-Blockers and Mortality After Myocardial Infarction. Arch Intern Med. 1987;147(1):33-34. doi:10.1001/archinte.1987.00370010037007