title: The role of superior vena cava in catheter ablation of long-standing persistent atrial fibrillation.
abstract: OBJECTIVE
  The superior vena cava (SVC) has been established as an important source of atrial fibrillation (AF). The role of SVC in long-standing persistent AF and the efficacy of empiric electrical isolation of the SVC are still unclear. The purpose of this study was to judge the role of SVC in catheter ablation of long-standing persistent AF.
  
  
  RESULTS
  A total of 102 consecutive patients with long-standing persistent AF were enrolled. All patients underwent circumferential pulmonary vein isolation, complex fractionated atrial electrograms ablation, and linear ablation during the index procedure. Superior vena cava-triggered AF and an SVC associated with the maintenance of AF were evaluated by mapping catheters during the procedure. The arrhythmogenicity of the SVC was confirmed in only 1 of the patients (0.98%). At the end of 12 months follow-up, the arrhythmia-free survival rate after a single procedure was 43.1%. After the last procedure (mean 1.47 ± 0.58 procedures), sinus rhythm was maintained in 71 (69.6%) patients, 63 of whom without antiarrhythmic drugs. The patients in AF recurrence group had higher rates of right atrium enlargement (71 vs. 34%, P = 0.03), ≥2 procedures (65 vs. 34%, P < 0.05), longer AF duration (84 ± 46 vs. 45 ± 34 months, P < 0.05), and larger left atrium diameter (50 ± 5 vs. 45 ± 6 mm, P < 0.05). In the multivariate analysis, left atrium diameter and AF duration were independent predictors of AF recurrence.
  
  
  CONCLUSIONS
  The arrhythmogenic SVC is rarely detected in patients with long-standing persistent AF. Empiric SVC electrical isolation in the stepwise approach of long-standing persistent AF seems unnecessary.
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiaotong University, No. 241 West Huaihai Road, Xu Hui District, Shanghai 200030, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Xu
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiaotong University, No. 241 West Huaihai Road, Xu Hui District, Shanghai 200030, China.
authors.forename: Yuanlong
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiaotong University, No. 241 West Huaihai Road, Xu Hui District, Shanghai 200030, China.
authors.forename: Shaohui
authors.initials: S
authors.lastname: Wu
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiaotong University, No. 241 West Huaihai Road, Xu Hui District, Shanghai 200030, China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiaotong University, No. 241 West Huaihai Road, Xu Hui District, Shanghai 200030, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiaotong University, No. 241 West Huaihai Road, Xu Hui District, Shanghai 200030, China.
authors.forename: Weifeng
authors.initials: W
authors.lastname: Jiang
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiaotong University, No. 241 West Huaihai Road, Xu Hui District, Shanghai 200030, China.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiaotong University, No. 241 West Huaihai Road, Xu Hui District, Shanghai 200030, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Liu
mesh_terms: D000200:Action Potentials; D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods*; D016009:Chi-Square Distribution; D002681:China; D018572:Disease-Free Survival; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006339:Heart Rate; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D011667:Pulmonary Veins / Q000503:physiopathology / Q000601:surgery*; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D019564:Unnecessary Procedures; D014683:Vena Cava, Superior / Q000503:physiopathology / Q000601:surgery*
keywords: Atrial fibrillation; Catheter ablation; Superior vena cava