Abstract 4365866: Beta-Blocker Therapy After Acute Myocardial Infarction in Patients with Mildly Reduced or Preserved Ejection Fraction: An Updated Meta-Analysis

Background: Current guidelines recommend beta-blocker use after myocardial infarction (MI), however, Recent data has challenged the utility of beta-blockers in patients with preserved (LVEF>50%) or mildly reduced left ventricular ejection fraction (LVEF 40-50%) post the reperfusion era.This updated meta-analysis aims to update the current understanding of the efficacy of beta-blocker use after MI in patients undergoing primary percutaneous coronary intervention (PCI). Methods: A comprehensive literature review conducted across PubMed, ClinicalKey, and Cochrane from 2010 to 2024 identified five trials (n=19318 patients) that evaluated beta-blocker therapy after MI in patients with LVEF ≥ 40. Fixed and random effect models with Mantel-Haenszel statistical method were used to calculate p-values, risk ratios, Z scores, and a 95% confidence interval on RevMan 7.14.0 software. Results: A non-significant trend favoring continuation of beta-blocker therapy compared to cessation for incidence of composite major cardiovascular events (MACE)(p=0.29) (RR=1.09[0.93, 1.27]), death from any cause (p=0.43) (RR=1.121[0.84, 1.50]), death from cardiac cause(p=0.39) (RR=1.24[0.76, 2.00]), MI (p=0.46) (RR=1.07[0.89, 1.30]), hospitalization for heart failure (p=0.23) (RR=1.22[0.88, 1.69]), and stroke (p=0.81) (RR=1.04[0.75, 1.43]). Conclusion: The findings of this study suggest that beta-blocker therapy after MI in patients with LVEF ≥ 40 does not significantly improve MACE, death from any cause, death from cardiac cause, hospitalization for heart failure and stroke. For this subgroup, these findings support a more selective and individualized approach rather than routine post-MI beta-blocker prescription.