Intracardiac echocardiography guided anatomical approach to cardioneuroablation: feasibility and outcomes

Anatomical studies have documented a close topographical relationship between the ganglionated plexi (GP) containing parasympathetic inputs to the sinus node (SN) and atrioventricular node (AVN) and the epicardial fat pads (FPs) within the Waterston's interatrial groove. We aimed to investigate the feasibility and outcomes of a novel anatomical approach to cardioneuroablation (CNA) that targets the atrial areas adjacent to the interatrial FPs identified with intracardiac echocardiography (ICE).

About 17 patients [37.3 ± 10.2 years, 47% female] undergoing CNA for recurrent vasovagal syncope and documented sinus pauses (n = 13, 76%) and/or AVN block (AVB, n = 4, 16%) were included. The right superior RS-FP containing the RS-GP (target for SN vagal denervation) and the right inferior RI-FP containing the RI-GP (target for AVN vagal denervation) were identified with ICE and reconstructed on a 3D electroanatomic map. At baseline, all patients had provocable sinus pauses/AVB with extracardiac high-frequency vagal stimulation (ECVS). The target FPs could be identified in all patients and were adjacent to septal LA and RA sites covering an average surface area of 3.7 ± 1.4 cm2 and 2.97 ± 1.21 cm2, respectively. A total of 33 ± 15 RF ablations (30-40W, 60 s) were delivered to cover the target LA/RA area. A > 25% shortening of the PP interval was observed within the first 1-2 RF lesions in all cases. After ablation, complete abolition of sinus pauses/AVB response with ECVS was achieved in all patients, and 2 mg of atropine infusion resulted in no PP/PR interval change. After a median follow-up of 12 months (range 4-25 months), 16 patients (94%) remained free of recurrent symptoms (1 patient underwent repeat CNA for recurrent pre-syncope and AVB, 1 patient underwent PPM implant following ECG recording of asymptomatic diurnal AVB).

An ICE-guided anatomical approach to CNA targeting visible FPs at the Waterston's groove is a feasible and effective strategy to achieve SN/AVN vagal denervation, with good outcomes at mid-term follow-up.