Musings of a Cardiologist

In the latest annual scientific sessions at the ACC 24, the results from the REDUCE AMI trial have put the spotlight back on beta blockers, the age-old drug which has conventionally been used to treat post acute coronary syndrome patients. This registry-based randomized clinical trial, conducted among 5020 subjects, 95% of them being Swedish, led to the conclusion that long-term beta blocker therapy in subjects with acute coronary syndrome and a normal ejection fraction did not contribute to a reduced incidence of all-cause mortality and heart failure hospitalization.

The findings of the trial have, I daresay, limited the use of beta blockers in the patients with acute coronary syndrome and normal ejection fraction. This challenges the conventional wisdom of prescribing beta blockers in patients with no heart failure symptoms post-acute coronary syndrome. However, the importance of the beta blocker as a drug to prevent adverse ventricular remodeling in patients with low ejection fraction still holds true, and there are multiple trials to prove its efficacy. My chief concerns with the findings of the trial are, first and foremost, that this trial was conducted mainly among an ethnic population recruited from the SWEDEHEART registry. How much of this is applicable to other ethnicities still needs to be found out. Second, the study sample of 2508 patients undergoing beta blocker therapy is rather small to definitively derive any positive conclusions from it. Third, there was a significant crossover between the beta blocker and the non-beta blocker therapy group beyond 1 year, thus making it difficult to monitor drug adherence, which may have affected the final outcomes.

What this trial does prove is that more drugs are not usually better in the case of patients with acute coronary syndrome with preserved ejection fraction. Even though the drug may have been a cornerstone of heart failure therapy for years.