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Updated: Jul 10, 2026
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Post-Myocardial Infarction Heart Failure in Closed-chest Coronary Occlusion/Reperfusion Model in Göttingen Minipigs and Landrace Pigs
Published on: April 17, 2021
Beta-Blockers After Myocardial Infarction Without Reduced Ejection Fraction: A Meta-Analysis of Kaplan-Meier
Ameer Awashra1, Ahmed Emara2, Ahmed Mazen Amin3
1Department of Medicine, An-Najah National University, Nablus, Palestine.
Summary
Beta-blockers (β-blockers) do not improve outcomes for patients after myocardial infarction (MI) with preserved ejection fraction. Routine long-term use offers no prognostic advantage in this population.
Area of Science:
- Cardiology
- Clinical Trials
- Pharmacology
Background:
- Uncertainty surrounds long-term beta-blocker (β-blocker) benefits post-myocardial infarction (MI) in patients with preserved left-ventricular ejection fraction (LVEF ≥ 40%) in the current reperfusion era.
- Previous trials indicated mortality benefits, but modern treatments may alter these effects.
Purpose of the Study:
- To conduct a meta-analysis of randomized controlled trials (RCTs) evaluating beta-blockers (β-blockers) versus no beta-blockers in adults with MI and LVEF ≥ 40%.
- To assess the impact of beta-blockers on all-cause mortality, recurrent MI, and heart failure (HF).
Main Methods:
- Meta-analysis of five RCTs (n = 23,524 patients) identified through comprehensive database searches (PubMed, Scopus, Web of Science, Cochrane CENTRAL) up to October 2025.
- Individual patient data (IPD) reconstructed from Kaplan-Meier curves for time-to-event analysis.
- Pooled risk ratios (RRs) and hazard ratios (HRs) estimated using random-effects models, with Trial Sequential Analysis (TSA) and meta-regression performed.
Main Results:
- Beta-blockers (β-blockers) did not significantly reduce recurrent acute myocardial infarction (AMI) (HR: 0.89, P=0.1), heart failure (HF) (HR: 0.92, P=0.54), or all-cause mortality (HR: 0.97, P=0.63).
- Secondary endpoints, including major adverse cardiovascular events (MACE), cardiovascular death, stroke, and revascularization, showed no significant difference (P > 0.05).
- Trial sequential analysis (TSA) did not cross significance boundaries, and meta-regression revealed no significant effect modifiers; evidence certainty was rated low to moderate.
Conclusions:
- In patients with MI and preserved LVEF, beta-blockers (β-blockers) do not reduce mortality, ischemic events, or HF.
- Routine long-term use of beta-blockers (β-blockers) in this patient group provides no prognostic advantage.
- Beta-blocker (β-blocker) therapy should be reserved for specific indications like reduced LVEF, angina, arrhythmia, or hypertension.
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