Impact of left bundle branch block on heart failure with preserved ejection fraction.

BACKGROUND: The implications of LBBB in heart failure with preserved ejection fraction (HFpEF) is unclear. Our study assesses clinical outcomes among patients with LBBB and HFpEF who were admitted with acute decompensated heart failure.

METHODS: This is a cross-sectional study was conducted using the National Inpatient Sample (NIS) database from 2016-2019.

RESULTS: We found 74,365 hospitalizations with HFpEF and LBBB and 3,892,354 hospitalizations with HFpEF without LBBB. Patients with LBBB were older (78.9 vs 74.2 years) and had higher rates of coronary artery disease (53.05% vs 40.8%), hypertension (74.7% vs 70.8%), atrial fibrillation (32.8% vs 29.4%), sick sinus rhythm (3.4% vs 2.02%), complete heart block (1.8% vs 0.66%), ventricular tachycardia (3.5% vs 1.7%), and ventricular fibrillation (0.24% vs 0.11%). Patients with LBBB were found to have decreased in-hospital mortality (OR: 0.85; 0.76-0.96; p-0.009) but higher rates of cardiac arrest (OR: 1.39; 1.06-1.83; p-0.02) and need for mechanical circulatory support (OR: 1.7; 1.28-2.36; p-0.001). Patients with LBBB underwent a higher rate of pacemaker (OR: 2.98; 2.75-3.23; p < 0.001) and ICD (implantable cardioverter-defibrillator) placement (OR: 3.98; 2.81-5.62; p < 0.001). Patients with LBBB were also found to have a higher mean cost of hospitalization ($81,402 vs $60,358; p < 0.001) but lower length of stay (4.8 vs 5.4 days; p < 0.001).

CONCLUSION: In patients admitted with decompensated heart failure with preserved ejection fraction, left bundle branch block is associated with increased odds of cardiac arrest, mechanical circulatory support requirement, device implantation and mean cost of hospitalization but decreased odds of in-hospital mortality.