Cryoballoon cardioneuroablation: New electrophysiological insights

Background

Cardioneuroablation (CNA) targeting ganglionated plexi has shown promise in treating vasovagal syncope. Only radiofrequency ablation has been used to achieve this goal thus far.

Objective

The purpose of this study was to investigate the utility of cryoballoon ablation (CBA) of the pulmonary veins (PVs) as a potential simplified approach to CNA.

Methods

We report our observations of autonomic modulation in a series of 17 patients undergoing CBA for atrial fibrillation and our early experience using CBA of the PVs in 3 patients with malignant vagal syncope. In 17 patients undergoing CBA of AF, sinus cycle length was recorded intraprocedurally after ablation of individual PVs.

Results

The most pronounced shortening of the sinus cycle length was observed after isolation of the right upper PV, which was ablated last. Reduced sinus node recovery time and atrioventricular (AV) nodal effective refractory period were observed after CBA. Resting heart rate was elevated by 6–7 bpm after CBA and persisted during 12-month follow-up. CBA of the PVs was performed in 3 patients with recurrent vagal syncope mediated by sinus arrest (n = 2) and AV block (n = 1). In all patients, isolation of the right upper PV resulted in marked shortening of sinus cycle length. During follow-up of 178 ± 43 days (134–219 days), CNA resulted in abolition of pauses, bradycardia-related symptoms, and syncope in all patients.

Conclusion

CBA of the PVs (particularly the right upper PV) may be a predictable anatomic CNA approach in patients with refractory vagal syncope due to sinus arrest and/or AV block and may warrant systematic investigation as a tool to perform CNA.