Predictors of Clinical Success of Cardioneuroablation in Patients With Syncope: Results of a Multicenter Study.

Background: Cardioneuroablation (CNA) is a promising treatment for syncope.

Objectives: This study sought to analyze the success and risk of CNA ,and to describe predictive factors of CNA success in patients with syncope.

Methods: Seventy-seven consecutive patients with syncope treated with CNA in 22 hospitals and at least 6 months of follow-up were included. Patients with reflex cardioinhibitory, mixed syncope, functional sinus node dysfunction (SND), or functional atrioventricular block were included. The primary endpoint was the recurrence of syncope after the CNA.

Results: Mean age was 49.3 ± 13.4 years and 54.5% were women. Five (6.5%) patients presented complications. Three patients presented SND, 1 required a pacemaker. During a median follow-up of 12 months (Q1-Q3: 8-20 months), 26 (33.8%) patients had recurrence of syncope. Women had a significantly higher risk of recurrence compared with men (HR: 3.3; 95% CI: 1.2-8.8; P = 0.016). Patients >50 years of age had a significantly lower risk of recurrence compared with younger patients (HR: 0.3; 95% CI: 0.1-0.9; P = 0.032). The risk of recurrence in mixed syncope was significantly higher than in cardioinhibitory syncope (HR: 4.4; 95% CI: 1.1-17.5; P = 0.033). Syncope recurrence was significantly less frequent in patients treated with general anesthesia or deep sedation compared with conscious sedation (HR: 0.2; 95% CI: 0.1-0.6; P = 0.002). Finally, the number of radiofrequency applications (≤30 or >30) had a significant association with CNA success (HR: 0.4; 95% CI: 0.2-0.9; P = 0.042). These results were adjusted for confounding factors.

Conclusions: In this multicenter study, the effectiveness of CNA was less than previously reported. We found a 3.9% risk of SND. Male sex, age >50 years, cardioinhibitory syncope, general anesthesia or deep sedation, and >30 radiofrequency applications could predict success of CNA for syncope.