Beta-Blockers in Patients with Myocardial Infarction and Preserved Left Ventricular Ejection: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: The benefit of beta-blockers (BBs) for myocardial infarction (MI) patients with a preserved left ventricular ejection fraction (LVEF) is uncertain. While beneficial for a reduced LVEF, their efficacy with a preserved LVEF, especially with modern revascularization, is unclear. Methods: A PRISMA-guided systematic review and meta-analysis utilized PubMed and EMBASE. Three randomized controlled trials comparing outcomes in MI patients with a preserved LVEF treated with BBs versus no treatment were included. The primary outcome was composite all-cause mortality and MI; secondary outcomes were all-cause mortality, cardiovascular mortality, MI, and stroke. Results: Three studies, including a total of 9512 participants, were analyzed. Beta-blockers did not demonstrate a statistically significant benefit in reducing the composite endpoint of all-cause mortality and myocardial infarction (RR 0.97, 95% CI: 0.84-1.12, p = 0.671, I2 = 0%). Similarly, no significant effect was observed for secondary outcomes: all-cause mortality (RR 0.96, 95% CI: 0.79-1.17, p = 0.708), cardiovascular mortality (RR 1.22, 95% CI: 0.87-1.72, p = 0.247), myocardial infarction (RR 0.97, 95% CI: 0.78-1.19, p = 0.759), and stroke (RR 0.96, 95% CI: 0.66-1.38, p = 0.819). Conclusions: In patients with myocardial infarction and a preserved LVEF, beta-blockers did not significantly reduce mortality, recurrent myocardial infarction, or stroke, suggesting a limited benefit in this population under contemporary management protocols.