AbstractIntroductionHis bundle pacing (HBP) is the most physiologic form of pacing and has been associated with reduced risk for heart failure hospitalization (HFH) and mortality compared to right ventricular pacing. Left bundle branch area pacing (LBBAP) is a safe and effective alternative option for patients needing ventricular pacing. The aim of this study was to compare the clinical outcomes between LBBAP and HBP among a large cohort of patients undergoing permanent pacemaker implantation.MethodsThis observational registry included consecutive patients with AV block/AV node ablation who underwent de novo permanent pacemaker implantations with successful LBBAP or HBP between April 2018 and October 2020. The primary outcome was the composite endpoint of time to death from any cause or HFH. Secondary outcomes included the composite endpoint among patients with prespecified ventricular pacing burden and individual outcomes.ResultsThe study population included 359 patients who met the inclusion criteria (163 in the HBP and 196 in the LBBAP group). Paced QRSd during LBBAP was similar to HBP (125 ± 20.2 vs. 126 ± 23.5 ms, p = .643). There were no statistically significant differences in the primary composite outcome in LBBAP (17.3%) compared to HBP (24.5%) (hazard ratio [HR]: 1.15, 95% CI: 0.72–1.82, p = .552). Secondary outcomes of death (10% vs. 17%; HR: 1.3, 95% CI: 0.73–2.33, p = .38) and HFH (10% vs. 12%; HR: 1.02, 95% CI: 0.54–1.94, p = .94) were not different among both groups.ConclusionsThere were no statistically significant differences in the clinical outcomes of death or HFH in LBBAP when compared to HBP.