The benefits of beta-blockade at the time of myocardial infarction.

ABSTRACT

Data from the World Health Organization Monitoring Trends and Determinants in Cardiovascular Disease (WHO MONICA) project, collected in Perth, are described. Patients taking a beta-blocker at the time of onset of myocardial infarction are a high-risk group, but univariate analysis of the data showed that the overall survival of patients on beta-blockers at 28 days was the same as for those not taking beta-blockers. A multiple logistic regression model analysis showed that the patients treated with beta-blockers had a survival advantage at 28 days, with a relative risk of death of 0.5. The mechanism of benefit is unclear. It does not appear to be an anti-arrhythmic effect, because beta-blockers did not affect survival in the first 24 h following a myocardial infarction, nor did they affect ventricular fibrillation. The effect may be due to a reduction in myocardial necrosis. Furthermore, an analysis of the incidence of coronary disease and type of drugs prescribed in Perth has indicated that beta-blockers may be contributing to a decrease in mortality due to coronary events.