Circumferential Pulmonary Vein Isolation With the Cryoballoon Technique. Results From a Prospective 3-Center Study

Objectives: The purpose of this study was to investigate the efficacy safety of the novel cryoballoon device (Arctic Front, Cryocath, Quebec, Canada). Background: Antral pulmonary vein (PV) ablation with radiofrequency energy is widely used as a strategy for catheter ablation of paroxysmal atrial fibrillation (PAF). A novel double lumen cryoballoon catheter was designed for circumferential pulmonary vein isolation (PVI) with the cryoablation technique. Methods: We consecutively enrolled 346 patients with symptomatic, drug refractory paroxysmal (n = 293) or persistent (n = 53) atrial fibrillation (AF). In all patients, PVI of all targeted PVs was the therapeutic aim. The primary end points of this nonrandomized study were: 1) acute isolation rate of targeted PV; and 2) first electrocardiogram-documented recurrence of AF. The secondary end point was occurrence of PV stenosis or atrio-esophageal fistula. Results: The 1,360 of 1,403 PVs (97%) were targeted with balloons or balloons in combination with the use of Freezor Max (Cryocath). We found that ablation with the cryoballoon resulted in maintenance of sinus rhythm in 74% of patients with PAF and 42% of patients with persistent AF. No PV narrowing occurred. The most frequent complication was right phrenic nerve palsy observed during cryoballoon ablation at the right superior PV. Conclusions: Pulmonary vein isolation with a new cryoballoon technique is feasible. Sinus rhythm can be maintained in the majority of patients with PAF by circumferential PVI using a cryoballoon ablation system. Cryoablation was less effective in patients with persistent AF than in patients with PAF.