Pulmonary Vein Isolation Using a Second-Generation Cryoballoon in Patients With Paroxysmal Atrial Fibrillation: One-Year Outcome Using a Single Big-Balloon 3-Minute Freeze Technique.

Abstract

The second-generation cryoballoon (CB) has been recently introduced into clinical use for pulmonary vein isolation (PVI). Data on the feasibility, long-term outcome, and optimal freeze cycle are still limited. We assessed the 1-year clinical outcome after second-generation CB ablation with single 3-minute freeze techniques, and clinical variables associated with AF recurrence. A total of 108 paroxysmal atrial fibrillation (PAF) patients undergoing cryothermal PVI were enrolled. PVI was performed with one 28-mm CB using single 3-minute freeze techniques without bonus applications. Fourteen-day consecutive monitoring was done after discharge to detect early AF recurrences (ERAFs). Out of 425 PVs, 409 (96.2%) were isolated using exclusively CBs, and 16 required touch-up ablation. Transient phrenic nerve injury, pericardial tamponade, and 50% PV stenosis occurred in 9, 1, and 1 patients, respectively. No PV stenosis >50% was observed in any patients. The total procedure and fluoroscopic times were 82.9±26.4 and 26.2±14.8 minutes, respectively. ERAFs were detected in 51 (47.2%) patients. At 1-year after single and repeat procedures, 71.6% and 84.3% of the patients were free from recurrent AF off antiarrhythmic drugs (AADs), respectively. Eighteen patients underwent repeat procedures (median 6.0 [4.0-9.3] months post procedure), and 68.6% of PVs were still isolated. Cox's proportional models determined that ERAFs were significantly associated with AF recurrence (HR = 7.236; 95%CI = 2.753-19.016; P < 0.0001). AF-freedom off AADs at 1-year after single procedures was 90.8% and 50.3% in patients without and with ERAFs. Second-generation CB ablation using single 3-minute freeze techniques appears feasible in PAF patients. ERAFs were significant factors for predicting clinical outcomes.