title: Catheter ablation of atrial fibrillation: Radiofrequency catheter ablation for redo procedures after cryoablation.
abstract: OBJECTIVE
  To evaluate the effectiveness of two different strategies using radiofrequency catheter ablation for redo procedures after cryoablation of atrial fibrillation.
  
  
  METHODS
  Thirty patients (paroxysmal atrial fibrillation: 22 patients, persistent atrial fibrillation: 8 patients) had to undergo a redo procedure after initially successful circumferential pulmonary vein (PV) isolation with the cryoballoon technique (Arctic Front Balloon, CryoCath Technologies/Medtronic). The redo ablation procedures were performed using a segmental approach or a circumferential ablation strategy (CARTO; Biosense Webster) depending on the intra-procedural findings. After discharge, patients were scheduled for repeated visits at the arrhythmia clinic. A 7-day Holter monitoring was performed at 3, 12 and 24 mo after the ablation procedure.
  
  
  RESULTS
  During the redo procedure, a mean number of 2.9 re-conducting pulmonary veins (SD ± 1.0 PVs) were detected (using a circular mapping catheter). In 20 patients, a segmental approach was sufficient to eliminate the residual pulmonary vein conduction because there were only a few recovered pulmonary vein fibres. In the remaining 10 patients, a circumferential ablation strategy was used because of a complete recovery of the PV-LA conduction. All recovered pulmonary veins could be isolated successfully again. At 2-year follow-up, 73.3% of all patients were free from an arrhythmia recurrence (22/30). There were no major complications.
  
  
  CONCLUSIONS
  In patients with an initial circumferential pulmonary vein isolation using the cryoballoon technique, a repeat ablation procedure can be performed safely and effectively using radiofrequency catheter ablation.
authors.affiliation: Klaus Kettering, Felix Gramley, Department of Cardiology, University of Frankfurt, 60590 Frankfurt, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Kettering
authors.forename: Felix
authors.initials: F
authors.lastname: Gramley
keywords: Atrial fibrillation; Catheter ablation; Cryoablation; Pulmonary veins; Supraventricular arrhythmias