The need and duration of BB therapy in post MI patients with preserved left ventricular ejection fraction: a meta-analysis

Abstract

Background Oral beta-blockers have beneficial effect on long-term mortality in high-risk as low left ventricular ejection fraction (LVEF) patients with MI, but the effect and duration of use of Beta-blockers in post-AMI patients with preserved LVEF is still unknown. Methods We performed a systematic search in Cochrane library, Embase, Medline, Pubmed, Scopus, Web of Science, clinical trial registries, and for eligible studies (26,431 patients). Data for outcomes were pooled as Hazard ratios (HRs), with 95% confidence interval, using RevMan software for windows. Results The pooled effect-estimate showed significant decrease in all cause mortality in beta-blocker group (HR 0.71, 95% CI 0.62–0.82). A subgroup analysis regarding duration of use of BB (≤1 year or >1 year), age (≤65 or ≥65),sex, use of CCB, presence of HTN or DM, and LVEF (≥50 or ≥40) was done. No significant subgroup differences were detected: duration of use of BB (p=0.32), age (p=0.23), sex (p=0.84), CCBs (p=0.28), HTN (p=0.32), DM (p=0.92),and LVEF (p=0.06). No significant differences between bet-blocker vs. no beta-blockers in terms of cardiac death (HR 0.69, 95% CI 0.33–1.46), re-infarction (HR1.00, 95% CI 0.68–1.48), re-hospitalization (HR1.08, 95% CI 0.32–3.68), and revascularization (HR 0.94, 95% CI 0.76–1.16). Conclusion Beta-blockers might reduce mortality of post-AMI patients with preserved LVEF, but failed to prevent cardiac events. The upcoming trials (REBOOT, BETAMI, DANBLOCK, and ABYSS) will define the use of Beta-blockers in post AMI patients with preserved Left ventricular ejection fraction. FUNDunding Acknowledgement Type of funding sources: None.