title: Non-pulmonary vein epicardial foci of atrial fibrillation identified in the left atrium after pulmonary vein isolation.
abstract: BACKGROUND
  Pulmonary vein (PV) isolation (PVI) has been demonstrated to be an effective technique for curing atrial fibrillation (AF). AF foci that cannot be isolated by PVI (non-PV foci) can become the cause of AF recurrence. The purpose of this study was to investigate the characteristics of non-PV AF foci.
  
  
  RESULTS
  Two hundred consecutive patients with symptomatic AF underwent electrophysiologic studies. In all patients, successful ostial or antral PVI was achieved with a multielectrode basket catheter (MBC). In 45 patients, spontaneous AF was induced even after PVI. In 23 of those patients, 30 AF foci were found in the left atrium (LA) (12 in the PV antrum, and 18 in the LA wall). Twenty-six of those foci were eliminated by focal ablation guided by an MBC. Five of those foci (four in the PV antrum and one in the LA posterior wall) were speculated to be located epicardially because a small potential preceding the LA potential was recorded from the MBC electrodes during AF initiation at the successful ablation site where single large potentials were recorded during sinus rhythm and a longer duration of radiofrequency energy delivery was needed to eliminate them.
  
  
  CONCLUSIONS
  MBC mapping with induction of spontaneous AF may be useful for identifying non-PV AF foci in the LA after PVI. In some of those non-PV foci, mainly around the PVI lesions, a few electrophysiologic findings suggesting an epicardial location were observed. This may be a rationale for the efficacy of extensive PV ablation.
authors.affiliation: Division of Cardiovascular Diseases, University of Alabama at Birmingham, 1670 University Boulevard, Birmingham, AL 35294, USA. takumi-y@fb4.so-net.ne.jp
authors.forename: Takumi
authors.initials: T
authors.lastname: Yamada
authors.forename: Yoshimasa
authors.initials: Y
authors.lastname: Murakami
authors.forename: Taro
authors.initials: T
authors.lastname: Okada
authors.forename: Naoki
authors.initials: N
authors.lastname: Yoshida
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Ninomiya
authors.forename: Junji
authors.initials: J
authors.lastname: Toyama
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Yoshida
authors.forename: Naoya
authors.initials: N
authors.lastname: Tsuboi
authors.forename: Yasuya
authors.initials: Y
authors.lastname: Inden
authors.forename: Makoto
authors.initials: M
authors.lastname: Hirai
authors.forename: Toyoaki
authors.initials: T
authors.lastname: Murohara
authors.forename: Hugh T
authors.initials: HT
authors.lastname: McElderry
authors.forename: Andrew E
authors.initials: AE
authors.lastname: Epstein
authors.forename: Vance J
authors.initials: VJ
authors.lastname: Plumb
authors.forename: G Neal
authors.initials: GN
authors.lastname: Kay
mesh_terms: D000328:Adult; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000601:surgery*; D018780:Body Surface Potential Mapping / Q000379:methods*; D017115:Catheter Ablation / Q000379:methods*; D005260:Female; D006325:Heart Atria / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010496:Pericardium / Q000601:surgery; D011667:Pulmonary Veins / Q000601:surgery*; D055502:Secondary Prevention; D025321:Surgery, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome