Comparison of Clinical Outcomes Between Left Bundle Branch Area Pacing With a Stylet-Driven Lead and Conventional Right Ventricular Pacing.

BACKGROUNDS AND AIMS: Left bundle branch area pacing (LBBAP) has been shown to reduce the risk of pacing-facilitated heart failure (HF) compared to right ventricular pacing (RVP), but limited data exists comparing LBBAP with stylet-driven leads (SDL) and conventional RVP. The study aims to compare clinical outcomes between LBBAP using SDL and conventional RVP.

METHODS: From December 2018 to December 2023, patients who underwent pacemaker implantation at two tertiary hospitals were enrolled. Exclusions included those requiring cardiac resynchronization therapy and patients with ventricular pacing burden ≤ 10%. LBBAP was performed using SDL (Solia S60, Biotronik) with a fixed curve delivery sheath. Composite outcome I consisted of HF admission, pacing-induced cardiomyopathy (defined as an LVEF decline of ≥ 10% or below 50%), and upgrade to biventricular pacing. Composite outcome II included all-cause death in addition to the components of composite outcome I.

RESULTS: A total of 738 patients (mean age 72.1 years; 52% of men; 243 LBBAP vs. 495 RVP) were included. Atrioventricular block was more common pacing indication in LBBAP group than RVP group (88.1% vs. 69.3%, p < 0.001). Compared to RVP group, ventricular pacing burden was higher in the LBBAP group (96% vs. 86%, p < 0.001). LBBAP was associated with a lower risk of composite outcome I and II compared to RVP (adjusted HR 0.27 [95% confidence interval 0.11-0.68], p = 0.006 for composite outcome I, aHR 0.41 [0.20-0.84], p = 0.015 for composite outcome II), mainly driven by a lower risk of pacing-induced cardiomyopathy by 70%. There were no significant differences in procedure-related complications.

CONCLUSION: LBBAP with SDL was associated with a lower risk of adverse clinical outcomes compared to conventional RVP in patients requiring substantial ventricular pacing.