Comparison of clinical and echocardiographic outcomes between left bundle branch area pacing and right ventricular pacing in older patients.

Background: Left bundle branch area pacing (LBBAP) is safe and effective, but studies in older patients are lacking. This study compared the clinical and echocardiographic outcomes of LBBAP and right ventricular pacing (RVP) in patients aged ≥75 years.

Methods: This prospective observational study included older patients with symptomatic bradycardia who underwent LBBAP or RVP between 2019 and 2022. Clinical data, including pacing and electrophysiological characteristics, echocardiographic measurements, and device-related complications were collected. The primary endpoint was a composite of all-cause mortality, heart failure hospitalization, and upgrade to biventricular pacing. Secondary outcomes included changes in left ventricular ejection fraction (LVEF).

Results: Of 267 included patients, 110 underwent LBBAP and 157 underwent RVP. LBBAP was successful in 109 patients (success rate: 99.1%), with one patient eventually undergoing RVP. The pacing parameters of LBBAP were similar to those of RVP, except for a significantly narrower paced QRS duration (112.8 ± 11.6 vs. 138.3 ± 23.9 ms, p < .001). Ventricular lead implanting procedural duration was longer for LBBAP than RVP (14.0 vs. 6.0 min, p < .001), as was the fluoroscopy time (4.0 vs. 2.0 min, p < .001). During a mean follow-up period of 31.0 ± 16.8 months, the primary outcome incidence was significantly lower following LBBAP than RVP (15.1% vs. 21.1%; hazard ratio, 0.471; 95% confidence interval, 0.215-1.032; p = .036) in 149 patients (55.8%) with ventricular pacing burden > 20%. RVP reduced LVEF from 62.7 ± 4.1% at baseline to 59.8 ± 7.8% at the final follow-up (p = .001), whereas LBBAP preserved LVEF (61.4 ± 6.3% vs. 60.1 ± 7.4%, p = .429).

Conclusion: LBBAP demonstrated improved clinical outcomes compared with RVP and maintained LVEF in older patients with high ventricular pacing burdens.