Early Experience of Patients with left Bundle Branch Block Corrected through Left Bundle Branch Area Pacing Compared with Conventional Right Ventricular Pacing: A Single-Center Retrospective Study.

Background: Left bundle branch area pacing (LBBAP) has the advantages of narrow QRS duration, rapid peak left ventricular (LV) activation, and LV dyssynchrony correction with a low, stable pacing output. Here we report our experience with patients undergoing LBBAP with a left bundle branch block (LBBB) for clinically indicated pacemaker or cardiac resynchronization therapy implantation. We compared the initial follow-up data of these patients and patients undergoing conventional right ventricular pacing (RVP). Methods: This retrospective study was performed between January 2017 and December 2020 and recruited 19 consecutive patients (mean age: 63 years; 8 women, 11 men) who underwent LBBAP (13 LBBAP only and 6 LBBAP + LV pacing), and 14 consecutive patients (mean age: 75 years; 8 women, 6 men) who underwent RVP. Demographic data, QRS durations, and echocardiographic parameters were compared before and after the procedures. Results: LBBAP substantially shortened the QRS duration and improved LV dyssynchrony echocardiographic parameters. However, RVP was not significantly associated with prolonged QRS duration and worse LV dyssynchronization. LBBAP improved cardiac contractility in selected patients. We did not find adverse effects of LBBAP on patients with preserved systolic function, possibly due to the limited number of patients and follow-up time. However, two of the 11 patients with preserved systolic function at baseline who underwent conventional RVP developed heart failure after implantation. Conclusions: In our experience, LBBAP improves LBBB-related ventricular dyssynchrony. However, LBBAP requires greater skill, and doubts remain about lead extraction. LBBAP may be an option for patients with LBBB when performed by an experienced operator, however further studies are needed to verify our findings.