title: Role of high dominant frequency sites in nonparoxysmal atrial fibrillation patients: insights from high-density frequency and fractionation mapping.
abstract: BACKGROUND
  The adjunctive role of dominant frequency (DF) mapping during complex fractionated electrogram (CFE) ablation of atrial fibrillation (AF) has not been clarified.
  
  
  OBJECTIVE
  The purpose of this study was to investigate whether DF distribution or substrate properties are related to fibrillatory activity in the left atrium (LA) and to evaluate the effect of CFE ablation on the different patterns of DF distribution.
  
  
  METHODS
  The study enrolled 50 nonparoxysmal AF patients who underwent mapping, pulmonary vein isolation, and CFE ablation. High-density DF and CFE mapping were performed from the center of DF(max) centrifugally to the rest of the LA. The LA substrate was classified into two types depending on the presence of intra-LA DF gradients as type 1 (>20% of the average DF) or type 2 (<20% of the average DF).
  
  
  RESULTS
  In type 1, maximal CFE and DF gradients were observed at the boundary (n = 14) or center (n = 16) of the DF(max) region. In type 2 (n = 20), less intra-LA DF gradient was observed (4.27 +/- 1.92 Hz vs 1.14 +/- 0.52 Hz for types 1 and 2, P <.001) and a large proportion of continuous CFEs extended from the center of DF(max) (19% +/- 11% and 42% +/- 15% of the LA for types 1 and type 2, P = .001). The procedure termination rate and long-term sinus rhythm maintenance rate were lower in patients with a smaller DF gradient (P <.05).
  
  
  CONCLUSIONS
  The spatial distribution of fractionated activity was associated with particular DF patterns in nonparoxysmal AF patients. Patients with an evident intra-LA DF gradient responded better to pulmonary vein isolation and continuous CFE ablation.
authors.affiliation: Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Yenn-Jiang
authors.initials: YJ
authors.lastname: Lin
authors.forename: Hsuan-Ming
authors.initials: HM
authors.lastname: Tsao
authors.forename: Shih-Lin
authors.initials: SL
authors.lastname: Chang
authors.forename: Li-Wei
authors.initials: LW
authors.lastname: Lo
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Hu
authors.forename: Chien-Jung
authors.initials: CJ
authors.lastname: Chang
authors.forename: Wen-Chin
authors.initials: WC
authors.lastname: Tsai
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Suenari
authors.forename: Shih-Yu
authors.initials: SY
authors.lastname: Huang
authors.forename: Hsing-Ya
authors.initials: HY
authors.lastname: Chang
authors.forename: Tsu-Juey
authors.initials: TJ
authors.lastname: Wu
authors.forename: Shih-Ann
authors.initials: SA
authors.lastname: Chen
mesh_terms: D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D018780:Body Surface Potential Mapping; D017115:Catheter Ablation / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006325:Heart Atria / Q000503:physiopathology*; D006329:Heart Conduction System / Q000503:physiopathology* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D012815:Signal Processing, Computer-Assisted