Outcomes of left bundle branch area pacing compared to His bundle pacing as a primary pacing strategy: Systematic review and meta-analysis

Background: Novel pacing technologies, such as His bundle pacing (HBP) and left bundle branch area pacing (LBBaP), have emerged to maintain physiological ventricular activation. We investigated the outcomes of LBBP with HBP for patients requiring a de novo permanent pacing.Methods and Results: Systematic review of randomized clinical trials and observational studies comparing LBBaP with HBP until March 01, 2023 was performed. Random and fixed effects meta-analyses of the effect of pacing technology on outcomes were performed. Study outcomes included pacing metrics, QRS duration, lead revision, procedure parameters, all-cause mortality and heart failure hospitalization (HFH). Overall, 10 studies with 1596 patients were included. Implant success rate was higher in LBBaP compared with HBP (RR 1.24, 95% CI: 1.08 to 1.42, p = .002). LBBaP was associated with lower capture threshold at implantation (mean difference (MD) -0.62 V, 95% CI: -0.74 to -0.51 V, p < .0001) and at follow-up (MD -0.74 V, 95% CI: -0.96 to -0.53, p < .0001), shorter procedure duration (MD -14.66 min, 95% CI: -23.54 to -5.78, p = .001) and shorter fluoroscopy time (MD -4.2 min, 95% CI: -8.4 to -0.0, p = .05). Compared with HBP, LBBaP was associated with a decreased risk of all-cause mortality (RR: 0.50, 95% CI: 0.33 to 0.77, p = .002) and HFH (RR: 0.57, 95% CI: 0.33 to 1.00, p = .05). No statistical differences were found in lead revisions and QRS duration before and after pacing.Conclusion: This meta-analysis found that LBBaP was superior to HBP regarding pacing metrics and implant success rate as an initial pacing strategy, although absence of head-to-head randomized comparison warrants caution in interpretation of the results.