LBBP Outperforms Biventricular Pacing in Heart Failure: HeartSync Trial Findings
China: A recent randomized clinical trial published in JAMA Cardiology by Xueying Chen from Zhongshan Hospital, Fudan University, Shanghai, and colleagues has demonstrated that left bundle-branch pacing (LBBP) may offer better long-term outcomes than conventional biventricular pacing (BiVP) in patients with heart failure and left bundle-branch block (LBBB).
The findings suggest that LBBP could emerge as a promising alternative for patients with severely reduced left ventricular ejection fraction (LVEF).
Cardiac resynchronization therapy using BiVP has long been a standard approach for managing heart failure with electrical conduction abnormalities such as LBBB. However, LBBP has recently gained attention as a more physiological pacing strategy that directly engages the heart’s conduction system. Despite this growing interest, robust comparative data from randomized trials have been limited until now.
For this purpose, the researchers conducted a multicenter, prospective randomized clinical trial involving 200 patients across six centers in China. All participants had heart failure with LBBB and an LVEF of 35% or lower. Patients were randomly assigned in a 1:1 ratio to receive either LBBP or BiVP. The study spanned from October 2020 to September 2024, with a median follow-up duration of 36 months.
The primary outcome assessed was the time to all-cause death or hospitalization due to heart failure.
The trial revealed the following findings:
- LBBP was associated with a significantly lower incidence of the primary outcome compared to BiVP (8% vs 28%).
- This reflects a substantially reduced overall risk with LBBP.
- All-cause mortality was lower in the LBBP group (2% vs 5%), though the difference was not statistically significant.
- Heart failure–related hospitalizations were significantly reduced with LBBP (7% vs 28%).
- Overall echocardiographic response rates were similar between LBBP and BiVP groups.
- A greater proportion of patients receiving LBBP achieved a “super response,” indicating marked improvement in LVEF.
- Procedural success rates were high and comparable for both LBBP and BiVP.
Despite promising results, several limitations were noted. The study included only Chinese patients, with a higher prevalence of nonischemic cardiomyopathy, limiting generalizability. Procedures were conducted at experienced centers, which may affect reproducibility in routine settings. Additionally, the lack of detailed follow-up on left bundle capture and the absence of cardiac MRI data limited mechanistic insights.
Overall, the trial provides strong evidence that LBBP may be more effective than BiVP in reducing the combined risk of death and heart failure hospitalization in patients with LBBB and severely reduced LVEF. These findings support the consideration of LBBP as an alternative pacing strategy, although further large-scale studies are needed to validate its broader applicability.
Reference:
Chen X, Liu X, Li R, et al. Long-Term Outcomes of Left Bundle-Branch Pacing vs Biventricular Pacing in Heart Failure: The HeartSync-LBBP Randomized Clinical Trial. JAMA Cardiol. 2026;11(4):352–359. doi:10.1001/jamacardio.2026.0083
Next Story