title: Ablation of rotor and focal sources reduces late recurrence of atrial fibrillation compared with trigger ablation alone: extended follow-up of the CONFIRM trial (Conventional Ablation for Atrial Fibrillation With or Without Focal Impulse and Rotor Modulation).
abstract: OBJECTIVE
  The aim of this study was to determine if ablation that targets patient-specific atrial fibrillation (AF)-sustaining substrates (rotors or focal sources) is more durable than trigger ablation alone at preventing late AF recurrence.
  
  
  BACKGROUND
  Late recurrence substantially limits the efficacy of pulmonary vein isolation for AF and is associated with pulmonary vein reconnection and the emergence of new triggers.
  
  
  METHODS
  Three-year follow-up was performed of the CONFIRM (Conventional Ablation for Atrial Fibrillation With or Without Focal Impulse and Rotor Modulation) trial, in which 92 consecutive patients with AF (70.7% persistent) underwent novel computational mapping. Ablation comprised source (focal impulse and rotor modulation [FIRM]) and then conventional ablation in 27 patients (FIRM guided) and conventional ablation alone in 65 patients (FIRM blinded). Patients were followed with implanted electrocardiographic monitors when possible (85.2% of FIRM-guided patients, 23.1% of FIRM-blinded patients).
  
  
  RESULTS
  FIRM mapping revealed a median of 2 (interquartile range: 1 to 2) rotors or focal sources in 97.7% of patients during AF. During a median follow-up period of 890 days (interquartile range: 224 to 1,563 days), compared to FIRM-blinded therapy, patients receiving FIRM-guided ablation maintained higher freedom from AF after 1.2 ± 0.4 procedures (median 1; interquartile range: 1 to 1) (77.8% vs. 38.5%, p = 0.001) and a single procedure (p < 0.001) and higher freedom from all atrial arrhythmias (p = 0.003). Freedom from AF was higher when ablation directly or coincidentally passed through sources than when it missed sources (p < 0.001).
  
  
  CONCLUSIONS
  FIRM-guided ablation is more durable than conventional trigger-based ablation in preventing 3-year AF recurrence. Future studies should investigate how ablation of patient-specific AF-sustaining rotors and focal sources alters the natural history of arrhythmia recurrence. (The Dynamics of Human Atrial Fibrillation; NCT01008722).
authors.affiliation: Department of Medicine, University of California, San Diego, San Diego, California; Veterans Affairs Medical Center, San Diego, California. Electronic address: snarayan@ucsd.edu.
authors.forename: Sanjiv M
authors.initials: SM
authors.lastname: Narayan
authors.affiliation: Department of Medicine, University of California, San Diego, San Diego, California; Veterans Affairs Medical Center, San Diego, California.
authors.forename: Tina
authors.initials: T
authors.lastname: Baykaner
authors.affiliation: Veterans Affairs Medical Center, San Diego, California.
authors.forename: Paul
authors.initials: P
authors.lastname: Clopton
authors.affiliation: Department of Medicine, University of California, San Diego, San Diego, California; Veterans Affairs Medical Center, San Diego, California.
authors.forename: Amir
authors.initials: A
authors.lastname: Schricker
authors.affiliation: Department of Medicine, University of California, San Diego, San Diego, California; Veterans Affairs Medical Center, San Diego, California.
authors.forename: Gautam G
authors.initials: GG
authors.lastname: Lalani
authors.affiliation: Department of Medicine, University of California, San Diego, San Diego, California; Veterans Affairs Medical Center, San Diego, California.
authors.forename: David E
authors.initials: DE
authors.lastname: Krummen
authors.affiliation: University of California, Los Angeles, Los Angeles, California.
authors.forename: Kalyanam
authors.initials: K
authors.lastname: Shivkumar
authors.affiliation: The Krannert Institute of Cardiology, Indiana University, Indianapolis, Indiana.
authors.forename: John M
authors.initials: JM
authors.lastname: Miller
mesh_terms: D001281:Atrial Fibrillation / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011667:Pulmonary Veins / Q000601:surgery*; D055502:Secondary Prevention; D013997:Time Factors; D016896:Treatment Outcome
keywords: FIRM; ablation; atrial fibrillation; clinical trial; electrical rotors