title: Biatrial substrate properties in patients with atrial fibrillation.
abstract: BACKGROUND
  The atrial substrate plays an important role in the maintenance of atrial fibrillation (AF). Further investigation of the biatrial substrate may be helpful for understanding the mechanism of AF. The aim of this study was to investigate the properties of right and left atrial (RA and LA) substrate in AF patients and their impact on the catheter ablation.
  
  
  METHODS
  Biatrial electroanatomic mapping using a three-dimensional mapping system (NavX) was performed in 117 consecutive patients with paroxysmal (n = 99) and persistent (n = 18) AF. The biatrial voltage and total activation time (TAT) were obtained during sinus rhythm.
  
  
  RESULTS
  The LA had a lower voltage (1.6 +/- 0.5 vs 2.0 +/- 0.6 mV, P < 0.001) than the RA. The TAT correlated with the voltage (r = -0.65, P < 0.001). The patients with persistent AF had a lower atrial voltage, higher coefficient of variance for the LA voltage, longer LA TAT, and more extensive scar than those with paroxysmal. The patients with recurrent AF after catheter ablation had a lower LA voltage and higher incidence of LA scarring than those without recurrence. A scar located in the low anteroseptal or low posterior wall of LA was related to recurrence of AF. LA scarring was the independent predictor of AF recurrence after catheter ablation.
  
  
  CONCLUSIONS
  The LA voltage was lower than the RA, and the atrial voltage correlated with the TAT. Electroanatomical remodeling of the atria could be crucial to the maintenance of AF. The LA substrate properties may play an important role in the recurrence of AF after catheter ablation of AF.
authors.affiliation: Division of Cardiology and Cardiovascular Research Center, National Yang-Ming University, School of Medicine, and Taipei Veterans General Hospital, Taiwan.
authors.forename: Shih-Lin
authors.initials: SL
authors.lastname: Chang
authors.forename: Ching-Tai
authors.initials: CT
authors.lastname: Tai
authors.forename: Yenn-Jiang
authors.initials: YJ
authors.lastname: Lin
authors.forename: Wanwarang
authors.initials: W
authors.lastname: Wongcharoen
authors.forename: Li-Wei
authors.initials: LW
authors.lastname: Lo
authors.forename: Ta-Chuan
authors.initials: TC
authors.lastname: Tuan
authors.forename: Ameya R
authors.initials: AR
authors.lastname: Udyavar
authors.forename: Sheng-Hsiung
authors.initials: SH
authors.lastname: Chang
authors.forename: Hsuan-Ming
authors.initials: HM
authors.lastname: Tsao
authors.forename: Ming-Hsiung
authors.initials: MH
authors.lastname: Hsieh
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Hu
authors.forename: Yi-Jen
authors.initials: YJ
authors.lastname: Chen
authors.forename: Shih-Ann
authors.initials: SA
authors.lastname: Chen
mesh_terms: D001281:Atrial Fibrillation / Q000503:physiopathology* / Q000601:surgery; D018780:Body Surface Potential Mapping; D017115:Catheter Ablation; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D016896:Treatment Outcome