Left bundle branch area pacing in pediatric patients after surgical correction of congenital heart disease

Abstract Introduction 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). Pediatric CSP cases may be challenging due to small chamber sizes and lack of suitable tools. Another important question is complex anatomy after correction of congenital heart diseases. We present data of single-center experience of LBBAP in pediatric patients after surgical correction of CHD. Methods Inclusion criteria – patients under 18 years old with symptomatic bradycardia and previous CHD surgery. We collected baseline data, including previous medical history, pre-procedural electrocardiography (ECG) and transthoracic echocardiography (TTE), pacing parameters and procedural outcomes. Results Total 21 patients underwent implantation of LBBAP pacemaker. 9 (42%) patients had previous surgery for CHD. Mean age years 11,5±4,6 years. 5 boys and 4 girls. Mean weight 42,8±20,7 kg. Previous medical history included: Ebstein anomaly correction – 1 patient (11%), VSD plasty – 6 patients (66%), AV septal defect – 3 (33%), valvular surgery – 3 patients (33%), congenitaly corrected TGA – 1 patient (11%). In order to confirm left bundle branch area capture, peak left ventricular activation time (pLVAT) (73,4±3,9ms), V6-V1 (44,4±9,8 ms) interpeak interval, transition from non-selective to selective capture were recorded during the implantation. LBBAP resulted in narrow paced QRS duration (111,7±12,6 ms). Pacing parameters showed low thresholds (0,75±0,25V), stable impedance (561±78 Ohm). Mean procedure duration 107,2±39,6 min. Fluoroscopy time – 26,7±20 min. 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 2 patients we observed septal perforation, which was resolved by reposition of the lead. Conclusion LBBAP in pediatric patients appears as feasible and safe procedure with stable electrical parameters, resulting in narrow paced QRS duration. Difficult anatomy after CHD correction may impact to procedure failure or lack of conduction system capture criteria. 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.X-ray and ECG