title: A new approach for catheter ablation of atrial fibrillation: mapping of the electrophysiologic substrate.
abstract: OBJECTIVE
  We sought to test the hypothesis that complex fractionated electrograms (CFAEs) recorded during atrial fibrillation (AF) could be used as target sites for catheter ablation of AF.
  
  
  BACKGROUND
  Mapping of AF in humans has shown that areas of CFAEs correlate with areas of slowed conduction and pivot points of reentrant wavelets. We hypothesized that such areas of CFAEs could be identified in patients with AF and might serve as target sites for catheter ablation to maintain sinus rhythm.
  
  
  METHODS
  The study population included 121 patients (29 females; mean age, 63 years) with refractory AF (57 paroxysmal, 64 chronic). All patients underwent nonfluoroscopic electroanatomic mapping (CARTO) during AF. Using CARTO, the biatrial replica, displayed in a three-dimensional color-coded voltage map, was created during AF, and areas associated with CFAEs were identified. Radiofrequency ablation of the area with CFAEs was performed, aiming to eliminate CFAE and/or convert to sinus rhythm.
  
  
  RESULTS
  Complex fractionated atrial electrograms were found in seven of nine regions of both atria, but were mainly confined to the interatrial septum, pulmonary veins, roof of left atrium, and left posteroseptal mitral annulus and coronary sinus ostium. Ablations of the areas associated with CFAEs resulted in termination of AF without external cardioversion in 115 of the 121 patients (95%); 32 (28%) required concomitant ibutilide treatment. At the one-year follow-up, 110 (91%) patients were free of arrhythmia and symptoms, 92 after one ablation and 18 after two.
  
  
  CONCLUSIONS
  Areas with CFAEs represent a defined electrophysiologic substrate and are ideal target sites for ablations to eliminate AF and maintain normal sinus rhythm.
authors.affiliation: Pacific Rim Electrophysiology Research Institute, Inglewood, California 90301, USA. wee@pacificrimp.com
authors.forename: Koonlawee
authors.initials: K
authors.lastname: Nademanee
authors.forename: John
authors.initials: J
authors.lastname: McKenzie
authors.forename: Erol
authors.initials: E
authors.lastname: Kosar
authors.forename: Mark
authors.initials: M
authors.lastname: Schwab
authors.forename: Buncha
authors.initials: B
authors.lastname: Sunsaneewitayakul
authors.forename: Thaveekiat
authors.initials: T
authors.lastname: Vasavakul
authors.forename: Chotikorn
authors.initials: C
authors.lastname: Khunnawat
authors.forename: Tachapong
authors.initials: T
authors.lastname: Ngarmukos
mesh_terms: D001281:Atrial Fibrillation / Q000503:physiopathology* / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods*; D005260:Female; D006325:Heart Atria / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome