title: Catheter ablation of chronic atrial fibrillation targeting the reinitiating triggers.
abstract: BACKGROUND
  We assessed the mode of reinitiation of atrial fibrillation (AF) after cardioversion and the efficacy of ablating these foci of reinitiation in patients with chronic AF.
  
  
  RESULTS
  Fifteen patients, 7 with structural heart disease, underwent mapping and catheter ablation of drug-resistant AF documented to be persistent for 5 +/- 4 months. In all patients, cardioversion was followed by documentation of P on T atrial ectopy and early recurrence, which allowed mapping of the reinitiating trigger or the source of ectopy. Radiofrequency (RF) ablation was performed at pulmonary vein (PV) ostia using a target temperature of 50 degrees C and a power limit of 30 to 40 W, with the endpoint being interruption of all local muscle conduction. A total of 32 arrhythmogenic PVs and 2 atrial foci (left septum and left appendage) were identified: 1, 2, and 3 or 4 PVs in 5, 3, and 6 patients. RF applications at the ostial perimeter resulted in progressively increasing delay, followed by abolition of PV potentials in 8, but potentials persisted in 6. A single ablation session was performed in 7 patients and 8 underwent two or three sessions because of recurrence of AF; ablation was directed at the same source due to recovery of local PV potential or at a different PV. No PV stenosis was noted either acutely or at repeated follow-up angiograms. Nine patients (60%) were in stable sinus rhythm without antiarrhythmic drugs at follow-up of 11 +/- 8 months. Anticoagulants were interrupted in 7 patients.
  
  
  CONCLUSIONS
  PVs are the dominant triggers reinitiating chronic AF in this patient population. Elimination of PV potentials by ostial RF applications results in stable sinus rhythm in 60%. A larger group and longer follow-up are needed to investigate further the role of trigger ablation in curative therapy for chronic AF.
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, Bordeaux-Pessac, France.
authors.forename: M
authors.initials: M
authors.lastname: Haïssaguerre
authors.forename: P
authors.initials: P
authors.lastname: Jaïs
authors.forename: D C
authors.initials: DC
authors.lastname: Shah
authors.forename: T
authors.initials: T
authors.lastname: Arentz
authors.forename: D
authors.initials: D
authors.lastname: Kalusche
authors.forename: A
authors.initials: A
authors.lastname: Takahashi
authors.forename: S
authors.initials: S
authors.lastname: Garrigue
authors.forename: M
authors.initials: M
authors.lastname: Hocini
authors.forename: J T
authors.initials: JT
authors.lastname: Peng
authors.forename: J
authors.initials: J
authors.lastname: Clémenty
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000503:physiopathology* / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects; D002908:Chronic Disease; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000503:physiopathology / Q000601:surgery; D012449:Safety; D016896:Treatment Outcome