PO-699-02 CARDIONEUROABLATION: SELECTIVE TREATMENT OPTION FOR CARDIOINHIBITORY SYNCOPE

Abstract

Reflex cardioinhibitory syncope is common, and until recently, permanent pacemaker implantation was the only treatment option - and even then, an option with only modest efficacy in preventing recurrent syncope. Radiofrequency (RF) catheter ablation of epicardial ganglionated plexi (GP) is increasingly being explored as a therapeutic option. To assess the safety and efficacy of a consecutive group of patients (with a substantial rate of implantable monitoring follow-up) treated by cardio-neuroablation (CNA) in a single center. CNA is considered in pts after a positive atropine test. Under general anesthesia, electroanatomical LA / RA maps are created (CARTO, NavX). RF energy is applied to the GP predilection sites in both atria until the vagal response to high-frequency (HF) stimulation of the vagal nerve (at jugular vein level) is completely eliminated. A total of 31 patients (age 40.0 ± 8.5 yrs; 18 M / 13 W; BMI 26.6 ±4.9; normal LVEF and LA size) with cardioinhibitory syncope were treated with CNA. Three patients had prior pacemakers including two leadless pacers, and 15 pts (50%) had implantable loop recorders (ILRs). All patients had a positive atropine test pre-CNA. The indications for CNA were: syncope based on sinus bradycardia/arrest in 18 patient s, high degree AV block in 12 patients, and a combination of both in 1 patient. The average longest asystolic pause was 5 sec (range 3 - 40). The average number of syncopal events was 4 per patient (range 0-20). The median procedural time was 156 ± 46.9 min; the mean fluoroscopy time was 8.2 ± 4.4 min. Using a total of 28 ± 15 RF applications (total ablation time was 1736 ± 839 sec), the endpoint of abolishing any vagal response to HF stimulation was achieved in 100% of patients. There was one serious complication - a femoral artery pseudoaneurysm requiring surgery. During clinical follow-up (mean 10 months), including ILR interrogation, only 1 in 30 (3.3%) pts had recurrent syncope or significant bradycardia were. No patient required permanent pacing after CNA. Our observational study demonstrated that GP ablation is a safe procedure with an efficacy exceeding 95%. CNA should be evaluated in a randomized clinical trial.