Left bundle branch pacing versus biventricular pacing for cardiac resynchronization therapy: A systematic review and meta-analysis

Introduction: Cardiac resynchronization therapy (CRT) reduces heart failure (HF) hospitalization and all-cause mortality inHF patients with left bundle branch block (LBBB). Biventricular pacing (BVP) is the gold standard for achieving CRT, but about 30%–40% of patients do not respond to BVP-CRT. Recent studies showed that left bundle branch pacing (LBBP) provided remarkable results in CRT. Therefore, we conducted a meta-analysis aiming to compare LBBP-CRT versus BVP-CRT in HF patients. Methods:We systematically searched the electronic databases for studies published from inception to December 29, 2022 and focusing on LBBP-CRT versus BVP-CRT in HF patients. The primary endpoint was HF hospitalization. The effect size was estimated using a random-effect model as Risk Ratio (RR) and mean difference (MD). Results: Ten studies enrolling 1063 patients met the inclusion criteria. Compared to BVP-CRT, LBBP-CRT led to significant reduction in HF hospitalization [7.9% vs.14.5%; RR: 0.60 (95%CI: 0.39–0.93); p = .02], QRSd [MD: 30.26 ms (95%CI: 26.68–33.84); p < .00001] and pacing threshold [MD: −0.60 (95%CI: −0.71 to −0.48); p <.00001] at follow up. Furthermore, LBBP-CRT improved LVEF [MD: 5.78% (95%CI: 4.78–6.77); p < .00001], the rate of responder [88.5% vs.72.5%; RR: 1.19 (95%CI: 1.07–1.32); p = .002] and super-responder [60.8% vs. 36.5%; RR: 1.56 (95%CI: 1.27– 1.91); p < .0001] patients and the NYHA class [MD: −0.42 (95%CI: −0.71 to −0.14); p < .00001] compared to BVP-CRT. Conclusion: In HF patients, LBBP-CRT was superior to BVP-CRT in reducing HF hospitalization. Further significant benefits occurred within the LBBP-CRT group in terms of QRSd, LVEF, pacing thresholds, NYHA class and the rate of responder and super-responder patients.