Clinical implication of right bundle branch block in hospitalized patients with acute heart failure : data from the Korean Heart Failure (KorHF) registry

Abstract

Background:Conflicting data exist regarding the predictive value of bundle branch block (BBB) patterns for mortality in hospitalized patients with acute heart failure (AHF).Methods:Two thousand two hundred and two patients enrolled in the Korean Heart Failure (KorHF) Registry were analyzed to compare clinical outcomes among right BBB (RBBB, 5.4%), left BBB (LBBB, 4.9%), and no BBB (89.7%) on admission electrocardiogram. The primary composite endpoint was all-cause mortality or rehospitalization. The primary composite endpoint was all-cause mortality or rehospitalization.Results:During the median follow-up period of 572 days, the 3-year event rate of the composite endpoint was significantly higher in the patients with RBBB compared to those with LBBB or no BBB (65.1% vs. 49.9% vs. 49.3%, log-rank, p=0.004). Multivariate analysis demonstrated an increased risk of the composite endpoint for the patients with RBBB vs. LBBB (hazard ratio (HR)=2.57, p=0.001) and the patients with RBBB vs. no BBB (HR=1.91, p<0.001). In the reduced left ventricular ejection fraction (LVEF  40%), the risk of the composite endpoint was increased in the patients with RBBB vs. LBBB (for overall from HR 1.61, p=0.002 to HR=2.28, p=0.001).Conclusion: RBBB but not LBBB is a significant predictor of all-cause mortality or rehospitalization in hospitalized patients with AHF, especially with reduced LV systolic function.