Clinical outcomes of left bundle branch area pacing compared to right ventricular pacing: Results from the Geisinger-Rush Conduction System Pacing Registry

Abstract

BACKGROUND Left bundle branch area pacing (LBBAP) has been shown to be a feasible option for patients requiring ventricular pacing. OBJECTIVE The aim of this study was to compare clinical outcomes between LBBAP and RVP among patients undergoing pacemaker implantation METHODS: This observational registry included patients who underwent pacemaker implantations with LBBAP or RVP for bradycardia indications between April 2018 to Oct 2020. The primary composite outcome included all-cause mortality, heart failure hospitalization (HFH) or upgrade to biventricular pacing. Secondary outcomes included the composite endpoint among patients with a prespecified burden of ventricular pacing and individual outcomes. RESULTS A total of 703 patients met inclusion criteria (321 LBBAP and 382 RVP). QRSd during LBBAP was similar to baseline (121±23 vs 117±30ms, p=0.302) and was narrower compared to RVP (121±23 vs 156±27, p <0.001). The primary composite outcome was significantly lower with LBBAP (10.0%) compared to the RVP (23.3%) (HR 0.46, C.I. 0.306 to 0.695, p<0.001). Among patients with ventricular pacing burden >20%, LBBAP was associated with significant reduction in the primary outcome compared to RVP (8.4% vs 26.1%; HR: 0.32; C.I. 0.187 to 0.540, p<0.001). LBBAP was also associated with significant reduction in mortality (7.8% vs 15%, HR: 0.59, p=0.03) and HFH (3.7% vs 10.5%, HR: 0.38, p=0.004). CONCLUSIONS LBBAP resulted in improved clinical outcomes compared to RVP. Higher burden of ventricular pacing (>20%) was the primary driver of these outcome differences.