Beta-Blockers Hold No Mortality Benefit Following a Heart Attack

Sinai School of Medicine (New York, NY, USA) analyzed 60 randomized trials evaluating β-blockers use in MI. In all, 102,003 patients were included in the study, with 14 trials providing data on a follow-up longer than one year. The researchers evaluated the impact of contemporary treatment—reperfusion, aspirin, and statin—status on the association of early intravenous (IV) β-blocker use and outcomes in heart attack patients. The primary outcome was all-cause mortality.

The results showed that in acute MI, β-blockers reduced cardiovascular mortality, MI, and angina, in the pre-reperfusion era; there was no difference for other outcomes. In the reperfusion era, β-blockers reduced MI and angina, but at the expense of an increase in heart failure (HF) and cardiogenic shock, with no benefit for other outcomes. β-blockers held no mortality benefit in contemporary treatment of heart attacks. The study was published in the October 2014 issue of the American Journal of Medicine.

“In patients undergoing contemporary treatment, our data support the short-term [30 days] use of beta-blockers to reduce recurrent heart attacks and angina, but this has to be weighed at the expense of increase in HF, cardiogenic shock, and drug discontinuation, without prolonging life,” concluded lead author Sripal Bangalore, MD, MHA, of NYU Langone Medical Center, and colleagues. “The guidelines should reconsider the strength of recommendations for beta-blockers post myocardial infarction.”

β-blockers are used for the management of cardiac arrhythmias, protecting the heart from a second MI after a first heart attack (secondary prevention), and hypertension. They block the action of the endogenous catecholamines epinephrine and norepinephrine, in particular on adrenergic beta receptors located on cells of the heart muscles, airways, arteries, and other tissues that are part of the sympathetic nervous system. They also interfere with the binding to the receptor of other stress hormones, thus mediating the fight-or-flight response.

Related Links:
NYU Langone Medical Center
Mt. Sinai School of Medicine