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

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 I2 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.