Circumferential pulmonary vein isolation with the cryoballoon technique

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.