Improved all-cause mortality with left bundle branch area pacing compared to biventricular pacing in cardiac resynchronization therapy: a meta-analysis

Background: Left bundle branch area pacing (LBBAP) has emerged as a physiological alternative pacing strategy to biventricular pacing (BIVP) in cardiac resynchronization therapy (CRT). We aimed to assess the impact of LBBAP vs. BIVP on all-cause mortality and heart failure (HF)-related hospitalization in patients undergoing CRT. Methods: Studies comparing LBBAP and BIVP for CRT in patients with HF with reduced left ventricular ejection fraction (LVEF) were included. The coprimary outcomes were all-cause mortality and HF-related hospitalization. Secondary outcomes included procedural and fluoroscopy time, change in QRS duration, and change in LVEF. Results: Thirteen studies (12 observational and 1 RCT, n = 3239; LBBAP = 1338 and BIVP = 1901) with a mean follow-up duration of 25.8 months were included. Compared to BIVP, LBBAP was associated with a significant absolute risk reduction of 3.2% in all-cause mortality (9.3% vs 12.5%, RR 0.7, 95% CI 0.57–0.86, p < 0.001) and an 8.2% reduction in HF-related hospitalization (11.3% vs 19.5%, RR 0.6, 95% CI 0.5–0.71, p < 0.00001). LBBAP also resulted in reductions in procedural time (mean weighted difference− 23.2 min, 95% CI − 42.9 to − 3.6, p = 0.02) and fluoroscopy time (− 8.6 min, 95% CI − 12.5 to − 4.7, p < 0.001) as well as a significant reduction in QRS duration (mean weighted difference:− 25.3 ms, 95% CI − 30.9 to − 19.8, p < 0.00001) and a greater improvement in LVEF of 5.1% (95% CI 4.4–5.8, p < 0.001) compared to BIVP in the studies that reported these outcomes. Conclusion: In this meta-analysis, LBBAP was associated with a significant reduction in all-cause mortality as well as HF-related hospitalization when compared to BIVP. Additional data from large RCTs is warranted to corroborate these promising findings. Graphical abstract: LBBP, left bundle branch area pacing; BIVP, biventricular pacing; RRR, relative risk reduction; ARR, absolute risk reduction; ms, milliseconds; LVEF, left ventricular ejection fraction; NYHA, New York Heart Association; min, minutes (Figure presented.)