A new, large meta-analysis shows more harm than benefit from β-blockers post-MI

Heart skips a beatβ-blockers have been a cornerstone in the treatment of heart attack survivors for more than a quarter of a century. However, many of the data predate contemporary medical therapy such as reperfusion (restoring blood flow to an organ or tissue), statins, and antiplatelet agents, and recent data have called the role of β-blockers into question. A new study published in The American Journal of Medicine evaluated the traditional management of these patients after their discharge from the hospital and in the light of changing medical treatment, focused on conventional treatment with β-blockers.

The study, led by Sripal Bangalore, MD, MHA, of the Cardiovascular Outcomes Research Group at the NYU Medical Center and colleagues analyzed fourteen randomized trials which provided data on over 20,000 patients who had follow-up longer were followed for over than one year. Trials were stratified into those that took place in the reperfusion era (more than 50% undergoing reperfusion or receiving aspirin/statin) and those that took place before the reperfusion era. The researchers evaluated the impact of the modern treatment algorithm: reperfusion/aspirin/statin, in their attempt to evaluate the association of β-blocker use and outcomes in heart attack patients; the role of early intravenous β-blocker; and the required duration of β-blocker use.

Their findings were surprising, given the standard approach to such patients over the preceding decades: They found that β-blockers have no mortality benefit in contemporary treatment of heart attacks.

Dr. Bangalore had this comment: "In patients undergoing contemporary treatment, our data support the short-term (30 days) use of β-blockers to reduce recurrent heart attacks and angina, but this has to be weighed at the expense of increase in heart failure, cardiogenic shock, and drug discontinuation, without prolonging life. The guidelines should reconsider the strength of recommendations for β-blockers post myocardial infarction."

The results of this study are hardly surprising. This class of drugs came under scrutiny in 2012. At that time, ACSH s Dr. Josh Bloom s opinion piece entitled Beta blockers are busted what happens next? in New Scientist Magazine examined just this.