title: Complete antral encirclement is not required for pulmonary vein isolation.
abstract: BACKGROUND
  Complete circumferential antral ablation may not be necessary for successful pulmonary vein (PV) isolation in patients with paroxysmal atrial fibrillation (AF).
  
  
  OBJECTIVE
  We examined the feasibility of a noncircumferential approach limited to segments of the antra required for PV-atrial conduction.
  
  
  METHODS
  During ablation for paroxysmal AF, each PV antrum was divided into six segments, and ablation was sequentially targeted to antral segments with the earliest activity until bidirectional isolation was achieved. Ablation at the ostium was avoided. Patients requiring complete circumferential ablation (circumferential group) were compared with those undergoing incomplete antral ablation (noncircumferential group) with respect to freedom from symptomatic atrial arrhythmia, procedure, and ablation times.
  
  
  RESULTS
  Ninety-nine patients underwent ablation with successful isolation of PVs (n = 37 circumferential; n = 62 noncircumferential). There were no significant differences in age, gender, AF duration, or LA size. Procedure time (202 ± 45 vs. 185 ± 47 minutes; P = .06) and ablation time (51 ± 15 vs. 41 ± 14 minutes; P = .004) were shorter in the noncircumferential group. During follow-up (12 ± 6 months), freedom from symptomatic recurrence was 73% in both groups (P = .97), with organized atrial tachycardia being more common in the circumferential group (P = .06). In 22 patients undergoing repeat study, PV reconnection was demonstrated in 82% and 81% of PVs in each group. Reconnection in the noncircumferential group occurred in previously ablated segments in 10 (77%) of 13 cases.
  
  
  CONCLUSIONS
  Noncircumferential antral ablation achieves similar success rates with shorter procedure and ablation times than circumferential ablation. Greater attention should be focused on producing permanent lesions rather than on completing antral encirclement after isolation is achieved.
authors.affiliation: Arrhythmia Service, University of Western Ontario, London, Ontario, Canada.
authors.forename: Raymond W
authors.initials: RW
authors.lastname: Sy
authors.forename: Lorne J
authors.initials: LJ
authors.lastname: Gula
authors.forename: Peter
authors.initials: P
authors.lastname: Leong-Sit
authors.forename: George J
authors.initials: GJ
authors.lastname: Klein
authors.forename: Raymond
authors.initials: R
authors.lastname: Yee
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Krahn
authors.forename: Cathy
authors.initials: C
authors.lastname: Bentley
authors.forename: Shakeeb
authors.initials: S
authors.lastname: Razak
authors.forename: Allan C
authors.initials: AC
authors.lastname: Skanes
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D022062:Electrophysiologic Techniques, Cardiac; D005240:Feasibility Studies; D005260:Female; D006325:Heart Atria / Q000033:anatomy & histology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000601:surgery*