title: Prospective randomized comparison between a fixed '2C3L' approach vs. stepwise approach for catheter ablation of persistent atrial fibrillation.
abstract: OBJECTIVE
  This prospective clinical trial was designed to evaluate the efficacy of an ablation strategy, namely '2C3L', in the treatment of persistent atrial fibrillation (AF); and to compare its efficacy with that of the 'stepwise' approach, which has been acknowledged as a promising ablation technique for persistent AF.
  
  
  RESULTS
  The '2C3L' technique is a fixed ablation approach consisting of bilateral circumferential pulmonary vein antrum isolation (PVAI) and three linear ablation lesion sets across the mitral isthmus, left atrial roof, and cavo-tricuspid isthmus. One hundred and forty-six patients with persistent AF were randomized to undergo ablation by using the '2C3L' or the 'stepwise' technique (n = 73, respectively). The primary endpoint was freedom from any atrial tachyarrhythmia off antiarrhythmic drug (AAD) after a single procedure at follow-up. Twelve months after a single procedure, there was no difference in sinus rhythm (SR) maintenance rate between the two groups (67% for '2C3L' vs. 60% for 'stepwise', P = 0.394; 95% confidence interval of between-group difference -8.7 to 22.4%). The procedure (222 ± 42 vs. 263 ± 41 min), fluoroscopy (41 ± 9 vs. 55 ± 8 min), and radiofrequency (RF) (107 ± 32 vs. 128 ± 38 min) time were significantly shorter in the '2C3L' group (all P < 0.001). At 25 ± 5 months after the first procedure, 57.5 and 52.1% of patients from the '2C3L' group and the 'stepwise' group were in SR off AAD (P = 0.494), respectively.
  
  
  CONCLUSIONS
  For catheter ablation of persistent AF, the '2C3L' strategy is a fixed approach associated with clinical efficacy similar to that of the 'stepwise' approach but with less RF delivery, fewer X-ray exposure, and shorter procedural time.
authors.affiliation: Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chao Yang District, Beijing 100029, China.
authors.forename: Jian-Zeng
authors.initials: JZ
authors.lastname: Dong
authors.affiliation: Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chao Yang District, Beijing 100029, China.
authors.forename: Cai-Hua
authors.initials: CH
authors.lastname: Sang
authors.affiliation: Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chao Yang District, Beijing 100029, China.
authors.forename: Rong-Hui
authors.initials: RH
authors.lastname: Yu
authors.affiliation: Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chao Yang District, Beijing 100029, China.
authors.forename: De-Yong
authors.initials: DY
authors.lastname: Long
authors.affiliation: Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chao Yang District, Beijing 100029, China.
authors.forename: Ri-Bo
authors.initials: RB
authors.lastname: Tang
authors.affiliation: Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chao Yang District, Beijing 100029, China.
authors.forename: Chen-Xi
authors.initials: CX
authors.lastname: Jiang
authors.affiliation: Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chao Yang District, Beijing 100029, China.
authors.forename: Man
authors.initials: M
authors.lastname: Ning
authors.affiliation: Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chao Yang District, Beijing 100029, China.
authors.forename: Nian
authors.initials: N
authors.lastname: Liu
authors.affiliation: Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chao Yang District, Beijing 100029, China.
authors.forename: Xing-Peng
authors.initials: XP
authors.lastname: Liu
authors.affiliation: Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chao Yang District, Beijing 100029, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Du
authors.affiliation: Cardiology Division, Department of Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, HKSAR, China.
authors.forename: Hung-Fat
authors.initials: HF
authors.lastname: Tse
authors.affiliation: Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chao Yang District, Beijing 100029, China chshma@vip.sina.com.
authors.forename: Chang-Sheng
authors.initials: CS
authors.lastname: Ma
mesh_terms: D000200:Action Potentials; D000328:Adult; D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D006328:Cardiac Catheterization / Q000009:adverse effects / Q000379:methods*; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology / Q000601:surgery*; D006339:Heart Rate; D006723:Hong Kong; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000503:physiopathology / Q000601:surgery; D061646:Operative Time; D011446:Prospective Studies; D011667:Pulmonary Veins / Q000503:physiopathology / Q000601:surgery; D015641:Radiography, Interventional; D012008:Recurrence; D013997:Time Factors; D016896:Treatment Outcome; D014261:Tricuspid Valve / Q000503:physiopathology / Q000601:surgery
chemical_list: D000889:Anti-Arrhythmia Agents
keywords: Atrial fibrillation; Catheter ablation; Complex fractionated atrial electrogram; Linear ablation; Pulmonary vein