Cardioneuroablation in pediatric patients with cardioinhibitory vasovagal syncope, functional sinus bradycardia or functional advanced atrioventricular block

Abstract Background Cardioinhibitory vasovagal syncope (VVS), functional sinus bradycardia (FSB), and atrioventricular block (FAVB) due to parasympathetic overactivity are common in children and may lead to syncope or cause some prodromal symptoms. However, it generally portends a benign prognosis; some patients may experience syncope due to prolonged asystolic episodes secondary to significant sinus pauses or paroxysmal atrioventricular block. Pacemaker (PM) implantation should be avoided in these patients due to potential complications and the need for multiple battery replacements throughout their life. Cardioneuroablation (CNA) is an alternative method involving ganglionated plexi ablation, which aims to eliminate the excessive activity of the parasympathetic tone. Purpose To assess the efficacy and safety of CNA in pediatric patients with VVS, FSB, or FAVB. Methods This is a single-center, case-series study in which patients with VVS, FSB, or FAVB 18 years of age or younger who underwent CNA between 2021 and 2024 were included. CNA was performed anatomically guided by an electro-anatomical system (Carto 3 system), and intracardiac echocardiography (ICE). Vagal denervation was confirmed by Extra-Cardiac Vagal Stimulation (ECVS) or indirectly by changes in electrophysiological parameters. Results Eighteen patients were included. The median age was 17 ± 1 years (range 14 - 18) years), and 12 (67%) were female. Fourteen patients had cardioinhibitory VVS, 1 patient had FSB, and 1 had patient FAVB. The mean number of syncope during the whole life was 27 (median: 7), and one year before the procedure number of syncope was 9 (median: 3). Apart from one patient who had Marfan syndrome, the remaining patients had no comorbidities. Three patients had PM implanted before CNA. Nine patients had injuries related to syncope. The mean asystole duration was 17 ± 9 s. During the 14-month follow-up (range: 2 - 45), the efficacy of CNA, means time to first syncope recurrence, after the first procedure was 94%. One patient had repeat CNA due to reinnervation and syncope recurrence and then modification of the sinus node due to inappropriate sinus tachycardia, which finally ended with PM implantation. PM was removed in one patient, the remaining 2 patients are awaiting for further evaluation and qualification for PM removal. No acute complications were noted. Conclusion CNA seems to be effective and safe method in pediatric patients with VVS, FSB or FAVB. However, longer follow-up is needed to confirm these findings.