The prognostic value of a new left bundle branch block in patients with acute myocardial infarction: A systematic review and meta-analysis

Abstract

Objective: To assess the prognostic value of new left bundle branch block (LBBB) in patients with acute myocardial infarction (AMI). Background: LBBB develops in many cardiac conditions, including AMI. The empirical evidence for the contribution of LBBB to mortality in AMI is not consistent. Methods: Medline, PubMed, CINAHL, and EMBASE were searched. Inverse variance meta-analysis was performed with odds ratios as the effect estimates. The I 2 statistic and risk of bias were assessed. Results: Eight studies involving 105,861 participants were eligible. New LBBB was associated with higher mortality at 30 days (OR: 2.10, 95% CI 1.27 to 3.48) and 1-year follow up (OR: 2.81, 95% CI 1.64 to 4.80), and increased heart failure risk (OR: 2.64, 95% CI 1.84 to 3.77). Conclusions: AMI patients with new LBBB are a high risk group and must be treated accordingly. Yet, more research is needed given the limitations of studies.