Implementation of left bundle branch area pacing in pediatric patients

Conduction system pacing (CSP) - novel pacing modality which rapidly develops during the last years and nowadays it used as a first-line approach in adults. Nowadays only limited data are available in conduction system pacing in pediatric population (≤ 18 years old). The largest cohort in pediatric His bundle pacing is 17 patients with promising results and low complication rate. In the field of LBBAP in pediatric patients, one of the largest cohort of 12 patients was reported by Wenlong in 2022 . In 2023 Li presented study of 21 young patients who underwent LBBAP. In this observational study we present single-center experience of LBBAP in pediatric patients.

Inclusion criteria – patients under 18 years old with symptomatic bradycardia due to AV block and SSS, and patients with pacing induced cardiomyopathy. We collected baseline data, including previous medical history, pre-procedural electrocardiography (ECG) and transthoracic echocardiography (TTE), pacing parameters and procedural outcomes.

Total 21 patients underwent implantation of LBBAP pacemaker. Success rate – 90% (19 patients). In order to confirm left bundle branch area capture, peak left ventricular activation time (pLVAT) (68.5±4.1ms), V6-V1 (38.5±2.5ms) interpeak interval, transition from non-selective to selective capture were recorded during the implantation. Mean paced QRS duration in patients with primary implanted pacemaker was (105,6±10,5 ms). LBBAP resulted in significant reduction QRS duration in patients with PICM from 161,5±28,2 to 115,16±6,8 ms. Pacing parameters showed low thresholds (0,87±0,25V), stable impedance (832±62 Ohm) and mean R-wave amplitude of 12,3±3,6 mV. Mean procedure duration 107,2±39,6 min. Fluoroscopy time – 26,7±20 min. In the group of primary implantation and group of patients with lead malfunction LV function remains stable during follow-up. There were no major complications such as stroke, acute coronary artery injury, coronary artery fistula, worsening of tricuspid regurgitation, post-operative lead dislodgement, loss of the left bundle branch capture were noted in any of the cases during implanting process and follow-up. In 3 patients we observed septal perforation, which was resolved by reposition of the lead.

LBBAP in pediatric patients appears as feasible and safe procedure, resulting narrow QRS, preserving ventricular synchrony with stable electrical parameters. Due to small cohort of patients, further collaborative large studies are needed to evaluate long-term outcomes. Collaboration between pediatric cardiologists, electrophysiologists, and researchers is essential to advance our understanding of LBBAP in pediatric patients and improve outcomes for children requiring cardiac pacing.

Clinical examples of patients with LBBAP