Pulmonary vein isolation and beyond: Predictive value of vagal reactions in second-generation cryoballoon ablation for the outcome of persistent atrial fibrillation.

BACKGROUND

Cryoballoon ablation (CBA) is gaining increasing acceptance in the treatment of persistent (per) atrial fibrillation (AF). The cardiac autonomic nervous system plays a pivotal role in the regulation of AF.

OBJECTIVE

We evaluated the impact of vagal reactions (VRs), as a surrogate marker for autonomic nervous system modulation, on the outcome of CBA in patients (pts) with perAF.

METHODS

A total of 250 consecutive pts (mean age 63.9 ± 10.0 years; 175 pts, 70% male) undergoing primary second-generation CBA for perAF were studied. VRs were defined as bradycardia <40 beats/min, asystole, or higher-degree atrioventricular block. Follow-up visits at 3, 6, and 12 months included 7-day Holter electrocardiograms.

RESULTS

VRs were recorded in 61 pts (24%). These pts showed a significantly reduced recurrence rate of AF (5%) than did those without VRs (log-rank, P < .01). Univariate Cox regression analyses confirmed VRs as a strong predictor of AF-free survival (hazard ratio [HR] 0.10; P < .01). Female sex (HR 1.71; P = .02), preprocedural tachycardia (HR 1.01; P = .01), and AF (HR 1.75; P = .01) before CBA at admission were revealed as predictors of AF recurrence. Multivariate regression model calculation solely identified VRs (HR 0.11; 95% confidence interval 0.03-0.34; P < .01) and male sex (HR 0.57; 95% confidence interval 0.36-0.89; P = .01) as independent predictors of AF-free survival.

CONCLUSION

VR is an independent predictor of AF-free survival after CBA for perAF.