title: Spatial Relation Between Left Atrial Anatomical Contact Areas and Circular Activation in Persistent Atrial Fibrillation.
abstract: Atrial low-voltage zones (LVZs) may be related to maintenance of atrial fibrillation (AF). The influence of left atrial (LA) contact areas (CoAs) on reentrant or rotor-like sources maintaining AF has not been investigated.
  
  
  
  Forty patients with persistent AF (PsAF) were analyzed. Three representative CoA regions in the LA (ascending aorta: anterior wall; descending aorta: left inferior pulmonary vein; and vertebrae: posterior wall) were visualized by enhanced CT. Using circular catheters, the LVZs (<0.5 mV) were assessed after restoration of SR, and local activation mapping and frequency domain analyses were performed after induction of AF. Circular activation during AF was visually defined as sites with ≥2 rotations by serial electrograms encompassing >80% of the mean AF cycle length. A pivot was defined as the core of the localized circular activation. Anterior (39/40 patients, 98%), left pulmonary vein antrum (27/40, 68%), and posterior (19/40, 48%) CoAs were identified, and 80% (68/85) of those sites were overlapped by or close (<3 mm) to LVZs. Thirty-six (90%) patients demonstrated circular activation (3.1±1.7 sites/patients) along with significantly higher organized dominant frequencies (6.3 ± 0.5 Hz, regularity-index: 0.26 [0.23-0.41]) within the LA, and the average electrogram amplitude of those pivots was 0.30 mV (0.18-0.52). Of those sites, 55% (66/120) were located at or close to CoA regions. Catheter ablation including of LVZs neighboring CoAs terminated AF in 9 (23%) patients.
  
  
  
  External anatomical structures contacting the LA may be related to unique conduction properties in diseased myocardium necessary for PsAF maintenance.
authors.affiliation: Department of Cardiology, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan.
authors.forename: Shiro
authors.initials: S
authors.lastname: Nakahara
authors.affiliation: Department of Cardiology and Clinical Examination, Oita University, Oita, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Yamaguchi
authors.affiliation: Department of Cardiology, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Hori
authors.affiliation: Department of Cardiology, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan.
authors.forename: Naofumi
authors.initials: N
authors.lastname: Anjo
authors.affiliation: Department of Cardiology, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Hayashi
authors.affiliation: Department of Cardiology, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan.
authors.forename: Sayuki
authors.initials: S
authors.lastname: Kobayashi
authors.affiliation: Department of Cardiology, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Komatsu
authors.affiliation: Department of Cardiology, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan.
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Sakai
authors.affiliation: EP Expert Doctors-Team Tsuchiya, Kumamoto, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Fukui
authors.affiliation: EP Expert Doctors-Team Tsuchiya, Kumamoto, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tsuchiya
authors.affiliation: Department of Cardiology, Dokkyo Medical University Koshigaya Hospital, Saitama, Japan.
authors.forename: Isao
authors.initials: I
authors.lastname: Taguchi
mesh_terms: D000200:Action Potentials; D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery; D016279:Atrial Function, Left; D017115:Catheter Ablation; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D006329:Heart Conduction System / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
keywords: atrial fibrillation; catheter ablation; circular activation; low-voltage region