Key Points:
- Mixed trial results on beta-blockers post-MI.
- The biggest benefit is LVEF 40–49%.
- Experts call for personalized therapy.
Two large clinical trials presented at the European Society of Cardiology (ESC) Congress 2025 have reignited debate on the use of beta-blockers after heart attack in patients recovering from myocardial infarction (MI) who maintain a preserved left ventricular ejection fraction (LVEF).
The REBOOT-CNIC trial, involving more than 8,400 patients, found no overall benefit of beta-blocker therapy in post-MI patients with an LVEF above 40%. In contrast, the BETAMI-DANBLOCK trial, which studied over 5,500 patients, reported a reduction in major cardiovascular events, including recurrent MI and death, among those treated with beta-blockers.
Despite the apparent contradiction, researchers argue the findings converge on an important message: patients with mildly reduced LVEF, between 40% and 49%, may benefit most from continued therapy.
Subgroup Insights and Meta-Analysis
Both trials performed subgroup analyses pointing toward improved outcomes in patients with borderline heart function. In REBOOT-CNIC, while the overall results were neutral, a trend emerged suggesting that patients with mildly reduced LVEF experienced fewer adverse events. BETAMI-DANBLOCK showed a slightly larger benefit in the same subgroup, particularly in reducing recurrent heart attacks.
A meta-analysis pooling data from REBOOT-CNIC, BETAMI-DANBLOCK, and prior studies reinforced this conclusion. Across nearly 1,900 patients with mildly reduced LVEF, beta-blockers after heart attack lowered the risk of death, recurrent MI, or heart failure by about 25%.
“This is the first convincing evidence that beta-blockers provide meaningful protection in patients whose heart function is impaired, but not severely,” said Dr. Eva Prescott, co-principal investigator of BETAMI-DANBLOCK.
Implications for Guidelines and Practice
Current American and European guidelines broadly recommend beta-blockers after heart attack, though much of the supporting evidence predates modern reperfusion techniques and guideline-directed therapy. Recent studies, including the 2024 REDUCE-AMI trial, have questioned whether all patients with preserved LVEF truly benefit long-term.
“These new findings suggest a more personalized approach,” said Dr. Borja Ibáñez, principal investigator of REBOOT-CNIC. “Rather than prescribing beta-blockers to nearly everyone after MI, physicians should tailor treatment to patients with signs of heart dysfunction.”
Experts caution that while the data support benefit in select subgroups, the absolute risk reductions remain modest. In BETAMI-DANBLOCK, 48 patients would need to be treated over 3.5 years to prevent one adverse event. Nonetheless, in the context of modern cardiac care, even small gains can be meaningful when applied to millions of patients worldwide.
Moving Toward Personalized Therapy
Specialists emphasize the importance of individualized decision-making. Patients with preserved heart function (LVEF ≥ 50%) may not need long-term beta-blockers after heart attack, while those with mildly reduced function could see real benefits. For patients with significant heart damage (LVEF < 40%), beta-blockers remain a cornerstone of therapy.
“If the heart works well, beta-blockers seem unnecessary. But when function is slightly compromised, the drugs can make a difference,” said Dr. Filippo Crea of the Catholic University in Rome.
As research continues, physicians are encouraged to reassess beta-blocker use in stable patients several months after an MI, balancing benefits with side effects and quality-of-life considerations.
