title: A novel finding of the atrial substrate properties and long-term results of catheter ablation in chronic atrial fibrillation patients with left atrial spontaneous echo contrast.
abstract: BACKGROUND
  The atrial substrate in chronic atrial fibrillation (AF) patients with a left atrial spontaneous echo contrast (LASEC) has not been previously reported. The aim of this study was to investigate the atrial substrate properties and long-term follow-up results in the patients who received catheter ablation of chronic AF.
  
  
  METHODS
  Of 36 consecutive patients with chronic AF who received a stepwise ablation approach, 18 patients with an LASEC (group I) were compared with 18 age-gender-left atrial volume matched patients without an LASEC (group II). The atrial substrate properties including the weighted peak-to-peak voltage, total activation time during sinus rhythm (SR), dominant frequency (DF), and complex fractionated electrograms (CFEs) during AF in the bi-atria were evaluated.
  
  
  RESULTS
  The left atrial weighted bipolar peak-to-peak voltage (1.0 ± 0.6 vs 1.6 ± 0.7 mV, P = 0.04), total activation time (119 ± 20 vs 103 ± 13 ms, P < 0.001) and DF (7.3 ± 1.3 vs 6.6 ± 0.7 Hz, P < 0.001) differed between group I and group II, respectively. Those parameters did not differ in the right atrium. The bi-atrial CFEs (left atrium: 89 ± 24 vs 92 ± 25, P = 0.8; right atrium: 92 ± 25 vs 102 ± 3, P = 0.9) did not differ between group I and group II, respectively. After a mean follow-up of 30 ± 13 month, there were significant differences in the antiarrhythmic drugs (1.1 ± 0.3 vs 0.7 ± 0.5, P = 0.02) needed after ablation, and recurrence as persistent AF (92% vs 50%, P = 0.03) between group I and group II, respectively. After multiple procedures, there were more group II patients that remained in SR, when compared with group I (78% vs 44%, P = 0.04).
  
  
  CONCLUSIONS
  There was a poorer atrial substrate, lesser SR maintenance after catheter ablation and need for more antiarrhythmic drugs in the chronic AF patients with an LASEC when compared with those without an LASEC.
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Beny
authors.initials: B
authors.lastname: Hartono
authors.forename: Li-Wei
authors.initials: LW
authors.lastname: Lo
authors.forename: Chen-Chuan
authors.initials: CC
authors.lastname: Cheng
authors.forename: Yenn-Jiang
authors.initials: YJ
authors.lastname: Lin
authors.forename: Shih-Lin
authors.initials: SL
authors.lastname: Chang
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Hu
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Suenari
authors.forename: Cheng Hung
authors.initials: CH
authors.lastname: Li
authors.forename: Tze-Fan
authors.initials: TF
authors.lastname: Chao
authors.forename: Shuen-Hsin
authors.initials: SH
authors.lastname: Liu
authors.forename: Ya-Lei
authors.initials: YL
authors.lastname: Niu
authors.forename: Hung-Yu
authors.initials: HY
authors.lastname: Chang
authors.forename: Kibos
authors.initials: K
authors.lastname: Ambrose
authors.forename: Wen-Chung
authors.initials: WC
authors.lastname: Yu
authors.forename: Tsui-Lieh
authors.initials: TL
authors.lastname: Hsu
authors.forename: Shih-Ann
authors.initials: SA
authors.lastname: Chen
mesh_terms: D000368:Aged; D001146:Arrhythmia, Sinus / Q000503:physiopathology; D001281:Atrial Fibrillation / Q000000981:diagnostic imaging* / Q000601:surgery*; D016279:Atrial Function, Left / Q000502:physiology; D018780:Body Surface Potential Mapping; D017115:Catheter Ablation; D002908:Chronic Disease; D017548:Echocardiography, Transesophageal; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging* / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000000981:diagnostic imaging; D018570:Risk Assessment; D016019:Survival Analysis; D016896:Treatment Outcome