title: Comparisons of the underlying mechanisms of left atrial remodeling after repeat circumferential pulmonary vein isolation with or without additional left atrial linear ablation in patients with recurrent atrial fibrillation.
abstract: BACKGROUND
  Radiofrequency catheter ablation (RFCA) is a potentially curative treatment for atrial fibrillation (AF), however, whether or not additional left atrial (LA) linear ablation for recurrent AF adversely affects LA remodeling is unknown.
  
  
  METHODS
  Thirty-eight patients experiencing AF recurrence after the 1st circumferential pulmonary vein isolation (CPVI) underwent a repeat RFCA, including 20 and 18 patients receiving a repeat CPVI (group I) or CPVI plus LA linear ablation (group II), respectively. 2-D echocardiography was performed during sinus rhythm within 24h, at 1-m and 6-m after RFCA. Longitudinal strains and strain rate were measured with speckle-tracking echocardiography. The standard deviation of contraction duration was defined as LA mechanical dispersion.
  
  
  RESULTS
  One and two patients experienced AF recurrence after the 2nd RFCA in group I and II, respectively (P=NS). The 1st CPVI with AF recurrence did not reduce LA size significantly in two groups. After a repeat CPVI, LA diameter but not LA maximal and minimal volume was significantly reduced in group I; additional LA linear ablation significantly decreased LA diameter, maximal and minimal volume in group II. However, there was no significant difference in LA emptying function, global and segmental LA strain and strain rate among the baseline, 1-m and 6-m follow-up in two groups. RFCA did not significantly increase LA mechanical dispersion regardless of the AF ablation strategies.
  
  
  CONCLUSIONS
  In patients with recurrent AF, a successful repeat CPVI with or without additional LA linear ablation reduced LA size without significant deleterious effects on LA function and mechanical dispersion.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Taiwan.
authors.forename: Chia-Hung
authors.initials: CH
authors.lastname: Yang
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Taiwan; Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors.forename: Chung-Chuan
authors.initials: CC
authors.lastname: Chou
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Taiwan; Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors.forename: Kuo-Chun
authors.initials: KC
authors.lastname: Hung
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Taiwan; Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors.forename: Ming-Shien
authors.initials: MS
authors.lastname: Wen
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Taiwan.
authors.forename: Po-Cheng
authors.initials: PC
authors.lastname: Chang
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Taiwan.
authors.forename: Hung-Ta
authors.initials: HT
authors.lastname: Wo
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Taiwan; Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors.forename: Cheng-Hung
authors.initials: CH
authors.lastname: Lee
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Taiwan; Chang Gung University College of Medicine, Taoyuan, Taiwan. Electronic address: capful36@gmail.com.
authors.forename: Fen-Chiung
authors.initials: FC
authors.lastname: Lin
mesh_terms: D001281:Atrial Fibrillation / Q000503:physiopathology / Q000601:surgery*; D064752:Atrial Remodeling / Q000502:physiology*; D017115:Catheter Ablation / Q000379:methods*; D018619:Echocardiography, Doppler, Pulsed; D005260:Female; D005500:Follow-Up Studies; D006325:Heart Atria / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D006329:Heart Conduction System / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000601:surgery*; D012008:Recurrence; D012189:Retrospective Studies; D013997:Time Factors
keywords: 2-D strain echocardiography; Atrial fibrillation; Radiofrequency ablation; Speckle-tracking echocardiography