title: Radiofrequency catheter ablation for redo procedures after pulmonary vein isolation with the cryoballoon technique : Long-term outcome.
abstract: BACKGROUND
  Catheter ablation has become the first line of therapy in patients with symptomatic, recurrent, drug-refractory atrial fibrillation (AF). Cryoablation has been shown to be a safe and effective technique for pulmonary vein (PV) isolation. However, the arrhythmia recurrence rate is high after cryoablation procedures. Radiofrequency catheter ablation has been shown to be an effective strategy for redo procedures in these patients and to provide a favourable outcome during midterm follow-up. The aim of this study was to analyse whether the strategy also provides favourable results during long-term follow-up (5 years).
  
  
  METHODS
  In this study 30 patients (paroxysmal AF: 22 patients, persistent AF: 8 patients) underwent a redo procedure after initially successful circumferential PV isolation with the cryoballoon technique (Arctic Front Balloon, Medtronic). The redo ablation procedures were performed using a segmental approach or a circumferential ablation strategy (CARTO; Biosense Webster, Diamond Bar, CA, USA) depending on the intraprocedural findings.
  
  
  RESULTS
  During the repeat procedure, a mean number of 2.9 reconnected PV (SD ± 1.0) were detected. In 20 patients, a segmental approach was sufficient to eliminate the residual PV conduction because only a few PV fibres were recovered (1-3 reconnected PV; group A). In the remaining 10 patients, a circumferential ablation strategy was used because of a complete recovery of the pulmonary vein - left atrial (PV-LA) conduction (group B). All reconnected PV were isolated successfully again. A third or fourth ablation procedure had to be performed in 4 (3 and 1, respectively) patients (13.3%). At 5‑year follow-up, 66.7% of all patients were free from an arrhythmia recurrence (20 out of 30). There were no major complications during long-term follow-up.
  
  
  CONCLUSIONS
  In patients with an initial circumferential PV isolation using the cryoballoon technique, a repeat ablation procedure can be safely and effectively performed using radiofrequency catheter ablation providing good long-term follow-up results.
authors.affiliation: Department of Cardiology, University of Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany. Klaus.Kettering@t-online.de.
authors.forename: Klaus
authors.initials: K
authors.lastname: Kettering
authors.affiliation: HPK Heidelberger Praxisklinik für Innere Medizin, Kardiologie und Pneumologie, Heidelberg, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Gramley
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000601:surgery*; D017115:Catheter Ablation; D003452:Cryosurgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000601:surgery*; D012008:Recurrence; D012086:Reoperation; D016896:Treatment Outcome
keywords: Atrial fibrillation; Catheter ablation; Cryoablation; Pulmonary veins; Repeat ablation