Clinical Outcomes in Conduction System Pacing Compared to Right Ventricular Pacing in Bradycardia

BACKGROUND Conduction system pacing (CSP) provides more physiological ventricular activation than right ven-tricular pacing (RVP). OBJECTIVES This study evaluated the differences in clinical outcomes in patients receiving CSP and RVP. METHODS Consecutive patients with pacemakers implanted for bradycardia from 2016 to 2021 in 2 centers were prospectively followed for the primary composite outcome of heart failure (HF) hospitalizations, upgrade to biventricular pacing, or all-cause mortality, stratified by ventricular pacing burden (Vp). RESULTS Among 860 patients (mean age 74 +/- 11 years, 48% female, 48% atrioventricular block), 628 received RVP and 231 received CSP (95 His-bundle pacing, 136 left bundle branch pacing). The primary outcome occurred in 217 (25%) patients, more commonly in patients with RVP than CSP (30% vs 13%, P < 0.001). In multivariable analyses, CSP was independently associated with 47% reduction of the primary outcome (adjusted hazard ratio [AHR]: 0.53; 95% CI: 0.29-0.97; P = 0.04) and HF hospitalization alone (AHR: 0.40; 95% CI: 0.17-0.95; P = 0.04), among only patients with Vp >20%. The incidence of the primary outcome was highest among RVP with Vp >20% and lowest in CSP with Vp >20% (35% vs 10%, P < 0.001). Compared with RVP with Vp >20%, both CSP with Vp >20% (AHR: 0.51; 95% CI: 0.28-0.91; P = 0.02) and all patients with Vp <20% (AHR: 0.73; 95% CI: 0.54-0.99; P = 0.04) were independently associated with reduced primary outcome, driven primarily by reductions in HF hospitalizations (P < 0.05). Event-free survival was similar between CSP with Vp >20% and those needing <20% Vp. CONCLUSIONS CSP significantly reduced adverse clinical outcomes for bradycardic patients requiring ventricular pacing and should be the preferred pacing modality of choice. (c) 2023 by the American College of Cardiology Foundation.

Automated summary

This study evaluated the differences in clinical outcomes between two different methods of cardiac pacing. The results showed that His-bundle pacing significantly reduced the occurrence of adverse clinical outcomes and should be the preferred pacing modality.