title: Radiofrequency ablation of paroxysmal atrial fibrillation: factors determining long-term clinical efficacy.
abstract: BACKGROUND
  Most of the studies on this subject have reported predictors of recurrence of atrial fibrillation after catheter ablation with relatively short follow-up periods.
  
  
  OBJECTIVE
  To retrospectively evaluate predictors of long-term recurrence of paroxysmal atrial fibrillation (AF) in patients undergoing pulmonary vein isolation following one single procedure.
  
  
  METHODS
  The authors studied a total of 139 patients (102 men; mean age of 55 +/- 12 years) undergoing radiofrequency ablation using the ostial or extra-ostial techniques for left atrial approach, combined or not with cavotricuspid isthmus ablation (CTI). Pre, intra and post-ablation variables were evaluated using univariate and multivariate analyses to determine the predictors of recurrence of AF after one procedure.
  
  
  RESULTS
  After a 33 +/- 12-month follow-up, we observed that a longer time of history of AF, use of more antiarrhythmic drugs, and recurrence of AF within 60 days post-procedure increased the risk of long-term recurrence of AF. On the other hand, the association of atrial flutter and concomitant CTI ablation reduced the risk of recurrence of AF.
  
  
  CONCLUSIONS
  Clinical variables such as time of history of AF and a larger number of antiarrhythmic drugs already used influenced the outcomes of catheter ablation. In patients with associated atrial flutter, simultaneous CTI block significantly reduced the long-term recurrence of atrial fibrillation.
authors.affiliation: Instituto do Coração de São Paulo, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP - Brasil. sartini@hotmail.com
authors.forename: Raul José Pádua
authors.initials: RJ
authors.lastname: Sartini
authors.forename: Maurício Ibrahim
authors.initials: MI
authors.lastname: Scanavacca
authors.forename: Eduardo
authors.initials: E
authors.lastname: Sosa
authors.forename: Luiz Felipe
authors.initials: LF
authors.lastname: Moreira
authors.forename: Sissy
authors.initials: S
authors.lastname: Lara
authors.forename: Carina
authors.initials: C
authors.lastname: Hardy
authors.forename: Francisco
authors.initials: F
authors.lastname: Darrieux
authors.forename: Denise
authors.initials: D
authors.lastname: Hachul
mesh_terms: D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000188:drug therapy / Q000601:surgery; D001282:Atrial Flutter / Q000601:surgery; D017115:Catheter Ablation / Q000379:methods; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000601:surgery*; D012008:Recurrence; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000889:Anti-Arrhythmia Agents