208: Midterm follow-up of patients with paroxysmal and persistent atrial fibrillation after pulmonary vein isolation by cryoballoon ablation

IntroductionThe objective of this prospective study was to evaluate the midterm clinical outcomes of PV isolation, using a cryoballoon catheter in our center.MethodsBetween july 2006 and november 2011, 234 consecutive patients (age 56±11 years, 76% of men) with symptomatic paroxysmal (n =162) or persistent AF (n =72) underwent PV isolation with a 28mm or 23mm cryoballoon catheter. In case of AF reccurence, patients could have several procedures using cryoablation and/or PV isolation and additional linear lesions by radiofrequency. Follow-up with holter monitoring and phone calls were performed.ResultsWe successfully isolated 713 of 936 PV (76%). In 73 patients (31%), an irrigated-tip radiofrequency catheter was used to create a supplemental focal lesion after cryoapplication and 55 patients (24%) had cavo-tricuspid isthmus line. 28mm cryoballoon catheter was mostly used (141 procedures, 60%). The mean overall procedural duration was 178±36min (range 120-285), and mean duration of fluoroscopic exposure was 9±5min (range 3-27). Over a median period of 20 months (range 3-53), 12 patients were lost to follow-up, 4 patients were deceased. At 3 months of follow-up, 78% of patients with paroxysmal AF had remained recurrence free, vs. 69% of patients with persistent AF. Phrenic nerve palsy was the most frequent, although reversible complication. A left atrial flutter appeared in 23 cases (11%). Considering midterm outcomes, 68% of patients with paroxysmal AF and 62% of patients with persistent AF had no recurrence, after an average of 1.3 procedures. Looking at failures, only 10% of patients did not have any improvement after ablation. 52% of patients were free of AF without antiarrhythmic drugs and 36% of them had stopped anticoagulation.ConclusionPV isolation, using a cryoballoon catheter is a safe and effective strategy with a high rate of success. It can be an alternative to RF ablation but randomised comparisons are needed