title: Influence of left atrium anatomical contact area in persistent atrial fibrillation-relationship between low-voltage area and fractionated electrogram.
abstract: BACKGROUND
  Atrial low-voltage areas are suggested to be related to maintenance of atrial fibrillation (AF). The influence of the left atrium (LA) contact area (CoA) has not been investigated.
  
  
  RESULTS
  Twenty-two persistent AF patients underwent high-density mapping during AF and sinus rhythm (SR). Three representative CoA regions in the LA (ascending aorta: anterior wall; descending aorta: left inferior pulmonary vein [LIPV]; and vertebrae: posterior wall) were identified. Electrogram analysis of both high dominant frequency (high-DF; >8 Hz) and complex fractionated atrial electrogram (con-CFAE; <50 ms) regions during SR was done. The anatomical relationship between CoA and both the very low-voltage areas (vLVA; <0.2 mV) and high-frequency sources was determined. Forty-seven vLVA (194.4 cm(2)) and 60 CoA (337.0 cm(2)) were documented, and 32 vLVA directly overlapped CoA. The vLVA were preferentially found in the anterior (45%) and posterior (13%) walls of the LA, and in the LIPV (13%), and corresponded to CoA sites. The mean voltage during SR at high-DF sites was significantly lower than that at con-CFAE sites (0.62 vs.1.54 mV; P<0.0001). Seventy-two percent of high-DF sites overlapped CoA, while 54% of con-CFAE did. Furthermore, 44% of high-DF surface area directly overlapped CoA, while only 19% of con-CFAE did.
  
  
  CONCLUSIONS
  Very low-voltage regions had a strong association with CoA. Sites with CoA had a higher incidence of fractionated electrograms both during SR and AF.
authors.affiliation: Department of Cardiology, Dokkyo Medical University Koshigaya Hospital.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Hori
authors.forename: Shiro
authors.initials: S
authors.lastname: Nakahara
authors.forename: Tohru
authors.initials: T
authors.lastname: Kamijima
authors.forename: Naofumi
authors.initials: N
authors.lastname: Tsukada
authors.forename: Akiko
authors.initials: A
authors.lastname: Hayashi
authors.forename: Sayuki
authors.initials: S
authors.lastname: Kobayashi
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Sakai
authors.forename: Isao
authors.initials: I
authors.lastname: Taguchi
mesh_terms: D000368:Aged; D001011:Aorta / Q000503:physiopathology*; D001281:Atrial Fibrillation / Q000503:physiopathology*; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D006325:Heart Atria / Q000503:physiopathology; D006801:Humans; D008875:Middle Aged; D011667:Pulmonary Veins / Q000503:physiopathology*