214 Treatment of Atrial Fibrillation by Pulmonary Vein Isolation Using Cryotherapy Balloon Technique: feasibility, complications, and short-term outcome.

Background: Radiofrequency (RF) isolation of pulmonary veins (PVs) has emerged as an effective treatment for patients presenting drug refractory atrial fibrillation (AF). The objective of this study was to assess the feasibility, safety, and short-term outcome of pulmonary vein isolation (PVI) in paroxysmal and persistent AF patients with a new cryoballoon catheter technique (Arctic Front, Cryocath, Quebec, Canada). Methods: Between December 2007 and April 2009, 37 patients (25 males, mean age 56 years old) with symptomatic, drug refractory, paroxysmal (n= 36) or persistent (n= 1) AF underwent circumferential antral PVI using a double lumen 23 or 28 mm cryoballoon catheter. Before discharge, all patients were subjected to 24-hour Holter electrocardiograms, echocardiography, and esophageal endoscopy. In case of symptomatic recurrences, a second AF ablation aiming at PV isolation, was performed using RF catheter. Results: Out of 148 treated veins, 140 were completely isolated (94.6%). All PVs were completely isolated in 28/37 patients (75.6%). The number of balloon applications per vein was 2.18±0.69. The mean procedure and fluoroscopy time were 164.8±39.3 and 32.4±12.3 min respectively. Thirty-one patients were free of AF at hospital discharge (83.8%). No PV narrowing, atrio-esophageal fistula or thromboembolic event occurred. Three phrenic nerve palsy (8.1%) were observed after cryoapplication at the right superior PV. Two of them resolved immediately after cessation of cryoenergy, one resolved at 2 weeks. The most frequent complications were pericardial effusions (n=8) and groin hematoma (n= 3) or ecchymosis (n=6), all spontaneously reversible. Among the 15 patients seen at 4 months follow-up, all were AF free after one (n = 11) or two procedures (n= 4) without any antiarythmic drugs. Conclusion: Cryoballoon PVI appears as an effective and safe technique with a relatively high clinical success rate at short-term follow-up. [Copyright &y& Elsevier]