Low-dose beta-blocker therapy may be beneficial following myocardial infarction. Canadian researchers have found that low-dose beta-blocker treatment is associated with a lower rate of heart failure than high-dose treatment but with similar survival benefits.
Data on use of beta-blockers following MI in were collated from two databases by Dr Paula Rochon (Kunin-Lunenfeld applied research unit, University of Toronto) and colleagues. They found that, among 4,681 elderly patients, those prescribed high-dose beta-blocker therapy were more likely to be admitted to hospital for heart failure than those prescribed low-dose therapy. All doses of beta-blockers were beneficial in terms of reduction in risk of death.
The researchers comment that although beta-blockers are recommended for heart failure, fears that they precipitate acute episodes of heart failure prevent their routine use. They found that while beta-blockers lowered the rate of hospital admission for heart failure, higher doses were associated with a greater risk of heart failure. "Our findings support the need to initiate beta-blocker therapy, when indicated, in lower doses and to increase the dose gradually as tolerated," they say (Lancet 2000;356:639).