Is beta-blocker prescription necessary post-heart attack?

Heart attacks are a leading cause of death, and according to the American Heart Association (AHA), more than 600,000 people experience their first heart attack each year. Beta-blockers are commonly prescribed following a heart attack to reduce the risk of a subsequent cardiovascular event. While beta-blockers are helpful for many reasons and can lower heart rate and blood pressure, there are some drawbacks to taking beta-blockers.

The REDUCE-AMI trial investigated whether beta-blockers decrease the risk of death or recurrent heart attacks in individuals with normal ejection fraction post-heart attack. Running from September 2017 to May 2023, the trial enrolled 5,020 participants from 45 healthcare centres. Participants had normal ejection fraction and underwent coronary angiography. They were randomly assigned beta-blockers (metoprolol or bisoprolol) for long-term treatment, with a median follow-up of 3.5 years.

The results showed that 7.9% of beta-blocker group had death or new heart attack, slightly lower than 8.3% in no-beta-blocker group. Beta-blockers didn't significantly reduce all-cause death: 3.9% in beta-blocker group vs. 4.1% in no-beta-blocker group.

The findings revealed no significant difference in cardiovascular outcomes between the beta-blockers group and the no-beta-blockers group.

“I do think the guidelines will be changed, and the prescription of beta-blockers will go down in patients with a heart attack (myocardial infarction) and a preserved (or normal) heart function, that is, about half of all patients with heart attack. However, for patients with reduced heart function or heart failure, we know that beta-blockers improve survival and symptoms. As a patient, you should never stop taking beta-blockers without first talking to your doctor,” said Tomas Jernberg, MD, PhD, a cardiology professor and Head of the Department of Clinical Sciences at Karolinska Institute in Sweden and Lead study investigator.

Reference: Troels Yndigegn, M.D., Bertil Lindahl, Ph.D., Katarina Mars, M.D., Joakim Alfredsson, Ph.D., Jocelyne Benatar, Ph.D., Lisa Brandin, Ph.D., David Erlinge, Ph.D, et al.; Beta-Blockers after Myocardial Infarction and Preserved Ejection Fraction; Journal: New England Journal of Medicine; DOI: 10.1056/NEJMoa2401479