title: Why atrial fibrillation recurs in patients who obtained current ablation endpoints with longstanding persistent atrial fibrillation.
abstract: OBJECTIVE
  Although several techniques for modification of atrial fibrillation (AF) substrate, such as linear ablation and complex fractionated atrial electrograms (CFAEs) ablation, have been proposed for longstanding persistent AF (LS-AF) and improved the outcome, there was still a certain recurrence rate, even if current ablation endpoints of these techniques were completely achieved. The purpose of this study was to describe the determinants of recurrent AF in patients who obtained current ablation endpoints with LS-AF.
  
  
  RESULTS
  In all, 208 consecutive patients who obtained current ablation endpoints with LS-AF were studied. The current ablation endpoints were defined as complete pulmonary vein isolation, bidirectional block of lines, and disappearance of CFAEs. After a follow-up of 19.9 ± 4.1 months, the patients were classified as AF recurrence group and non-AF recurrence group (including patients with sinus rhythm and atrial tachycardia), and 34 (16 %) patients were in the AF recurrence group. The patients in AF recurrence group had higher rates of right atrium (RA) enlargement (67.7 vs. 45.4 %, p = 0.018) and ≥2 procedure times (58.8 vs. 27.0 %, p < 0.001), longer AF duration (82.4 ± 44.8 vs. 50.8 ± 42.8 months, p < 0.001), and larger left atrium (LA) diameter (49.4 ± 6.2 vs. 46.5 ± 5.3 mm, p = 0.007). In the multivariate analysis, RA enlargement, ≥2 procedure times, and AF duration were independent predictors of AF recurrence.
  
  
  CONCLUSIONS
  RA enlargement, ≥2 procedure times, and AF duration played important roles in AF recurrence in patients who obtained current ablation endpoints. For these patients with AF recurrence who had already underwent ≥2 procedure times, enlarged RA may contribute to other AF foci and/or substrate, and the ablation strategy may be transformed from LA to RA in the next ablation procedures.
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital affiliated to Shanghai Jiaotong University, 241 West Huaihai Road, Shanghai, 200030, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhao
authors.forename: Weifeng
authors.initials: W
authors.lastname: Jiang
authors.forename: Li
authors.initials: L
authors.lastname: Zhou
authors.forename: Jun
authors.initials: J
authors.lastname: Gu
authors.forename: Yuanlong
authors.initials: Y
authors.lastname: Wang
authors.forename: Yugang
authors.initials: Y
authors.lastname: Liu
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Zhang
authors.forename: Shaohui
authors.initials: S
authors.lastname: Wu
authors.forename: Xu
authors.initials: X
authors.lastname: Liu
mesh_terms: D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control*; D017115:Catheter Ablation / Q000706:statistics & numerical data*; D002681:China / Q000453:epidemiology; D002908:Chronic Disease; D023381:Endpoint Determination / Q000379:methods* / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011667:Pulmonary Veins / Q000601:surgery*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018570:Risk Assessment; D055502:Secondary Prevention; D012680:Sensitivity and Specificity; D016896:Treatment Outcome