Abstract 12830: Cryoballoon Ablation vs. Radiofrequency Ablation of Pulmonary Veins after Failed Radiofrequency Ablation in Patients with Paroxysmal Atrial Fibrillation
Introduction: The aim of this prospective randomized double-blind study was to compare the efficacy and safety of cryoballoon (Cryo) ablation versus radiofrequency (RF) of PAF after failed first RF ablation.
Methods: Patients with a history of symptomatic PAF and after a previous failed first RF ablation procedure were eligible for this study. Patients were randomized to Cryo or RF. The primary end-point of the study was recurrence of atrial tachyarrhythmia, including AF and left atrial flutter/tachycardia, after a second ablation procedure. All patients were followed for 1 year. All patients were implanted with a cardiac monitor (Reveal XT, Medtronic) to continuously track the cardiac rhythm. Patients with an AF burden (AF%)≤0.5% were considered AF-free (Responders), while those with an AF%>0.5% were classified as patients with AF recurrences (non-Responders).
Results: Eighty patients with AF recurrences after a first RF pulmonary vein isolation (PVI) were randomized to Cryo (40) and to RF (40). Electrical potentials were recorded in 77 mapped PVs (1.9±0.8 per patient) in Cryo Group and 72 PVs (1.7±0.8 per patient) in RF Group (p=0.62), all of which were targeted with ablation. In Cryo group, 68 (88%) of the 77 PVs were isolated using only Cryo technique. The remaining nine veins were isolated using RF. One patient crossed-over to RF group from Cryo group. In RF group, all 72 veins were successfully isolated. The mean procedure duration and the fluoroscopy duration in the Cryo group were longer than in the RF group without reaching statistical significance (158 ± 42 minutes and 21±17 minutes; P = 0.16 and P = 0.28, respectively). At the 12-month follow-up examination, 23 (56%) of the 41 RF Group patients were AF-free (AF%≤0.5%). In contrast, in the Cryo Group, only 17 (44%) of the 39 patients were AF-free on no antiarrhythmic drugs (Log-rank test, p=0.11). There was no clinical relevant PV stenosis, cerebrovascular accident, atrio-esophageal fistula, or groin hematoma in either group. At the end of the follow-up, 20 (59%) of the 34 RF PVI only patients and 11 (38%) of the 29 Cryo PVI only patients were AF-free (Log-rank test, p=0.021).
Conclusion: RF might be preferred to Cryo as second ablation after failed first RF ablation in patients with PAF.
- © 2012 by American Heart Association, Inc.