The influence of metabolic syndrome on atrial fibrillation recurrence: five-year outcomes after a single cryoballoon ablation procedure

BACKGROUND: Metabolic syndrome (MetS) has been reported as a risk factor of atrial fibrillation (AF) recurrence after radiofrequency catheter ablation. This study aimed to investigate the long-term influence of MetS on paroxysmal AF recurrence after a single cryoballoon ablation procedure, which was scarcely investigated yet in Chinese population. METHODS: In total, 137 paroxysmal AF patients who had successfully completed a single cryoballoon ablation procedure at Fuwai Hospital, Beijing, China from December 2013 to October 2015 were enrolled. Excepting for patients with AF recurrence, all patients were followed up for no less than five years. Independent predictors of AF recurrence were determined by Cox proportional hazards regression analysis. RESULTS: Among 137 paroxysmal AF patients, 91 patients (66.4%) had successfully achieved overall five-year follow-up after a single cryoballoon ablation procedure, and 44 patients (32.1%) had MetS. Patients with MetS had a significant lower incidence of freedom from AF recurrence than those without MetS (50.0% vs. 74.2%, log-rank P < 0.01) during the five-year follow-up. MetS (HR = 1.95, 95% CI: 1.069−3.551, P = 0.030) was an independent predictor of AF recurrence after adjusting for multiple factors. After the second year post cryoballoon ablation procedure, the recurrence rate of AF gradually increased in patients with MetS, in contrast, decreased recurrence rate of AF in patients without MetS. CONCLUSIONS: MetS is an independent predictor for five-year AF recurrence after a single cryoballoon ablation procedure in paroxysmal AF patients. Combination therapy of AF and MetS may improve the long-term outcomes of AF patients.