title: Substrate and Trigger Ablation for Reduction of Atrial Fibrillation (STAR AF): a randomized, multicentre, international trial.
abstract: OBJECTIVE
  This multicentre, randomized trial compared three strategies of AF ablation: ablation of complex fractionated electrograms (CFE) alone, pulmonary vein isolation (PVI) alone, and combined PVI + CFE ablation, using standardized automated mapping software.
  
  
  RESULTS
  Patients with drug-refractory, high-burden paroxysmal (episodes >6 h, >4 in 6 months) or persistent atrial fibrillation (AF) were enrolled at eight centres. Patients (n = 100) were randomized to one of three arms. For CFE alone (n = 34), spontaneous/induced AF was mapped using validated, automated CFE software and all sites <120 ms were ablated until AF termination/non-inducibility. For PVI (n = 32), all four PV antra were isolated and confirmed using a circular catheter. For PVI + CFE (n = 34), all four PV antra were isolated, followed by AF induction and ablation of all CFE sites until AF termination/non-inducibility. Patients were followed at 3, 6, and 12 months with a visit, ECG, 48 h Holter. Atrial fibrillation symptoms were confirmed by loop recording. Repeat procedures were allowed within the first 6 months. The primary endpoint was freedom from AF >30 s at 1 year. Patients (age 57 +/- 10 years, LA size 42 +/- 6 mm) were 35% persistent AF. In CFE, ablation terminated AF in 68%. Only 0.4 PVs per patient were isolated as a result of CFE. In PVI, 94% had all four PVs successfully isolated. In PVI + CFE, 94% had all four PVs isolated, 76% had inducible AF with additional CFE ablation, with 73% termination of AF. There were significantly more repeat procedures in the CFE arm (47%) vs. PVI (31%) or PVI + CFE (15%) (P = 0.01). After one procedure, PVI + CFE had a significantly higher freedom from AF (74%) compared with PVI (48%) and CFE (29%) (P = 0.004). After two procedures, PVI + CFE still had the highest success (88%) compared with PVI (68%) and CFE (38%) (P = 0.001). Ninety-six percent of these patients were off anti-arrhythmics. Complications were two tamponades, no PV stenosis, and no mortality.
  
  
  CONCLUSIONS
  In high-burden paroxysmal/persistent AF, PVI + CFE has the highest freedom from AF vs. PVI or CFE alone after one or two procedures. Complex fractionated electrogram alone has the lowest one and two procedure success rates with a higher incidence of repeat procedures. ClinicalTrials.gov identifier number NCT00367757.
authors.affiliation: Southlake Heart Rhythm Program, Southlake Regional Health Centre, 105-712 Davis Drive, Newmarket, Ontario, Canada L3Y 8C3. atul.verma@utoronto.ca
authors.forename: Atul
authors.initials: A
authors.lastname: Verma
authors.forename: Roberto
authors.initials: R
authors.lastname: Mantovan
authors.forename: Laurent
authors.initials: L
authors.lastname: Macle
authors.forename: Guiseppe
authors.initials: G
authors.lastname: De Martino
authors.forename: Jian
authors.initials: J
authors.lastname: Chen
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Morillo
authors.forename: Paul
authors.initials: P
authors.lastname: Novak
authors.forename: Vittorio
authors.initials: V
authors.lastname: Calzolari
authors.forename: Peter G
authors.initials: PG
authors.lastname: Guerra
authors.forename: Girish
authors.initials: G
authors.lastname: Nair
authors.forename: Esteban G
authors.initials: EG
authors.lastname: Torrecilla
authors.forename: Yaariv
authors.initials: Y
authors.lastname: Khaykin
mesh_terms: D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012086:Reoperation; D016896:Treatment Outcome; D014859:Warfarin / Q000627:therapeutic use
chemical_list: D000925:Anticoagulants; D014859:Warfarin