title: Clinical outcome of left atrial ablation for paroxysmal atrial fibrillation is related to the extent of radiofrequency ablation.
abstract: BACKGROUND
  The exact mechanism of eliminating atrial fibrillation (AF) by catheter ablation techniques is not known. We investigated whether the extent of atrial damage conferred by radiofrequency lesions is a predictor of success after ablation, regardless of the method employed for ablation.
  
  
  METHODS
  Ninety consecutive patients with paroxysmal AF subjected to ostial-antral pulmonary vein isolation (n = 41) or circumferential (n = 49) catheter ablation were studied.
  
  
  RESULTS
  At 1 year follow-up, 16 out of 41 patients (39%) with ostial-antral ablation and 16 out of 49 patients (32.6%) with circumferential ablation had AF recurrences (p = 0.5). The mean duration of radiofrequency ablation lesions was statistically significantly shorter in patients with recurrence of AF compared to those with sinus rhythm 1 year after ablation (22.3 +/- 4.2 min vs. 27.2 +/- 4.5 min, respectively, p value < 0.001). Radiofrequency ablation time was inversely associated with the risk of recurrence of AF 1 year after ablation and this relationship remained even after adjustment for potential confounding factors such as age, sex, left atrial size, and type of ablation technique (ostial-antral or circumferential; HR = 0.80, 95% CI: 0.72-0.87, p < 0.001).
  
  
  CONCLUSIONS
  Duration of radiofrequency energy delivery is an independent predictor of clinical outcome at 1 year follow-up both among patients undergoing circumferential as well as ostial-antral ablation.
authors: Department of Cardiology, Athens Euroclinic, 9 Athanassiadou Street, Athens 11521, Greece. dkatritsis@euroclinic.gr
authors: Demosthenes
authors: D
authors: Katritsis
authors: Kenneth A
authors: KA
authors: Ellenbogen
authors: Eleftherios
authors: E
authors: Giazitzoglou
authors: Dimitrios
authors: D
authors: Sougiannis
authors: George
authors: G
authors: Paxinos
authors: Nicolaos
authors: N
authors: Fragakis
authors: A John
authors: AJ
authors: Camm
mesh_terms: D001281:Atrial Fibrillation / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D018572:Disease-Free Survival; D005260:Female; D006325:Heart Atria / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000601:surgery; D012008:Recurrence