β-blocker therapy results in a 25% reduction in the composite outcome of all-cause death, new myocardial infarction, or heart failure in patients with acute myocardial infarction and mildly reduced left ventricular ejection fraction (40-49%) without history or clinical signs of HF, a recent meta-analysis has reported.
This patient-level meta-analysis pooled data from four RCTs — REBOOT, BETAMI, DANBLOCK, and CAPITAL-RCT — conducted across five countries. It included 1,885 patients with LVEF 40–49% (median age 63 years) who had recent MI (≤14 days) without heart failure, randomized to β-blockers or no β-blockers, with a median follow-up of more than 1 year.Of these, 991 patients (53%) were randomized to β-blocker therapy and 894 (47%) to no β-blocker therapy, of whom 991 (53%) were randomized to β-blockers and 894 (47%) to no β-blockers, with a median follow-up of more than 1 year. The major beta-blocker noted in the study was metoprolol (49%). The findings were presented at the recently concluded ESC Congress 2025, Madrid, Spain; and have been published in The Lancet (August 2025).
The primary endpoint included a composite of all-cause death, new myocardial infarction, or heart failure. Key secondary endpoints included the individual components of the primary composite (all-cause death, new MI, heart failure), cardiac death, unplanned coronary revascularization, malignant ventricular arrhythmias, and safety outcomes, including stroke and advanced atrioventricular block.
Key results of the study are
- Primary outcome benefit: Over 3.5 years, β-blockers reduced the composite of death, new MI, or heart failure by 25% (HR 0.75, 95% CI 0.58–0.97; p=0.031), with consistent results across all four trials and countries. (Figure 1)
Figure 1: Cumulative incidence of primary endpoint
- Consistency and sensitivity: No heterogeneity was observed (I²=0%); findings were robust in sensitivity analyses and in patients with LVEF 41–49% (HR 0.73, p=0.037).
- Secondary outcomes: All outcomes trended lower with β-blocker therapy. All-cause death was reduced by 22% with β-blockers (58 vs 69; HR 0.78, 95% CI 0.55–1.11), recurrent MI by 23% (39 vs 46; HR 0.77, 0.50–1.18), heart failure by 29% (30 vs 39; HR 0.71, 0.44–1.14), and cardiac death by 45% (14 vs 23; HR 0.55, 0.28–1.06).
- Safety: Stroke (13 vs 7; HR 1.70, 0.68–4.25), advanced AV block (12 vs 11; HR 1.00, 0.44–2.27), and malignant ventricular arrhythmias (9 vs 5; HR 1.64, 0.55–4.89) were rare, with no significant safety concerns identified
- Subgroups: Benefits were most substantial in patients younger than 75 years, with a 35% lower risk (HR 0.65, 95% CI 0.47–0.90). No heterogeneity was seen by sex, MI type, LVEF subgroup, or country.
Overall, the findings support the use of β-blockers in patients with myocardial infarction and mildly reduced LVEF, highlighting their role as an effective long-term secondary prevention therapy.
This study expands the current evidence on the benefits of initiating β blockers in patients with recent myocardial infarction with reduced LVEF (≤40%) by demonstrating that those with mildly reduced LVEF (40–49%) also derive clinical benefit. Further research should focus on patients with preserved LVEF (≥50%)
Reference: Rossello X, Prescott EIB, Kristensen AMD, Latini R, Fuster V, Fagerland MW, et al. β blockers after myocardial infarction with mildly reduced ejection fraction: an individual patient data meta-analysis of randomised controlled trials. Lancet. 2025 Aug 30. doi: 10.1016/S0140-6736(25)01592-2. [Epub ahead of print]
Disclaimer: This website is primarily for healthcare professionals. The content here does not replace medical advice and should not be used as medical, diagnostic, endorsement, treatment, or prescription advice. Medical science evolves rapidly, and we strive to keep our information current. If you find any discrepancies, please contact us at corrections@medicaldialogues.in. Read our Correction Policy here. Nothing here should be used as a substitute for medical advice, diagnosis, or treatment. We do not endorse any healthcare advice that contradicts a physician's guidance. Use of this site is subject to our Terms of Use, Privacy Policy, and Advertisement Policy. For more details, read our Full Disclaimer here.
NOTE: Join us in combating medical misinformation. If you encounter a questionable health, medical, or medical education claim, email us at factcheck@medicaldialogues.in for evaluation.