764 CARDIONEUROABLATION OF VAGALLY MEDIATED BRADYARRHYTHMIA: A SINGLE-CENTER EXPERIENCE

Abstract

Abstract Background Cardioneuroablation (CNA) is a novel catheter-ablation technique for the treatment of vagally-mediated bradyarrhythmia including vaso-vagal syncope (VVS), functional atrioventricular block (AVB) and sinus node dysfunction (SND). CNA aims to blunt the cardioinhibitory reflex by eliminating postganglionic parasympathetic neurons in the atrial wall and ganglionated plexi (GPs). Early-phase studies have shown promising results, but clinical evidence remains limited. Purpose We present our single-center experience with CNA in the setting of VVS, symptomatic functional AVB, and SND. Methods Baseline and procedural characteristics, procedure-related complications, and clinical outcomes were collected in patients who underwent CNA from December 2018 to July 2022. The procedural workflow included an electroanatomic mapping-guided ablation strategy, which combines the bi-atrial 3D mapping with endocardial atrial bipolar electrograms (EGM), specifically targeting high-amplitude fractionated EGM. Results A total of 14 CNA procedures were performed in our center. Ablation indication was mainly VVS (57%), followed by AVB (29%) and SND (14%). Syncope was the most common symptom in our cohort (71%, burden of 7 per person-lifetime). Patients were young (43±16 years) and without structural heart disease (LVEF 58±4 ml, LAD 31±7 mm). Procedures were performed under general anesthesia, mean procedure time was 102±42 min, with minimal fluoroscopy dose (2.7±1.8 Gy/cm2). We observed 1 instance of post-ablation pericarditis and 2 sinus tachycardia which required medical treatment; no major adverse events occurred. Heart rate increased after ablation in all the patients, with a mean RR interval shortening of 28% and no further increase after atropine administration. Two patients had a recurrence at a median follow-up of 251 days (IQR: 118-536), both cases were syncopal events without documentation at loop-recorder of sinus bradycardia or atrial bradyarrhythmia. Conclusions CNA may be an alternative to pacemaker implantation in young, highly symptomatic patients, refractory to conventional therapies and without structural heart disease. Ablation is reasonably safe in experts’ hands, especially if compared with the long-life risk of device-related complications. Further large-scale randomized studies are needed to support these findings.