title: Stepwise linear approach to catheter ablation of atrial fibrillation.
abstract: BACKGROUND
  This study attempted to convert atrial fibrillation (AF) to sinus rhythm using a stepwise linear catheter ablation approach.
  
  
  METHODS
  One hundred and ninety-six patients (43 with persistent AF) were enrolled in the study. A multiple electrode array was used for anatomical navigation and activation mapping. Continuously incremental stimulation was used to induce AF if spontaneous AF was not present. Stepwise linear ablation was applied until AF was converted to sinus rhythm or atypical atrial flutter (AAFL) or atrial tachycardia (AT). The stepwise approach initially utilized a figure-7 lesion line between the right and left superior pulmonary vein on the roof of the left atrium and then extended along the ridge between the left appendage and the left pulmonary veins until the mitral valve annulus, as the primary lesions. If AF still persisted, high-frequency potentials in the inferior left atrium, coronary sinus, or right atrium were targeted. Noninducibility of AF was used as the end point.
  
  
  RESULTS
  AF was converted to sinus rhythm in 81.6% of patients (90.8% of paroxysmal and 51.1% of persistent AF, P<.01). The remainders of patients were converted to AAFL or AT. AF was terminated after ablation in right atrium in 7 patients. During an 18.2+/-7.3 month follow-up, 88.3% of patients were free of atrial tachyarrhythmias without medication, 9.7% of patients had refractory AAFL/AT, and only 2.1% of patients had paroxysmal AF.
  
  
  CONCLUSIONS
  Stepwise linear ablation is effective in converting AF to sinus rhythm and the figure-7 lesion line should be the basic lesion. Right atrium ablation is necessary in some patients.
authors.affiliation: Clinical EP Laboratory and Arrhythmia Service Center of Fuwai Heart Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China. ianyao@263.net.cn
authors.forename: Yan
authors.initials: Y
authors.lastname: Yao
authors.forename: Lihui
authors.initials: L
authors.lastname: Zheng
authors.forename: Shu
authors.initials: S
authors.lastname: Zhang
authors.forename: Ding Sheng
authors.initials: DS
authors.lastname: He
authors.forename: Kuijun
authors.initials: K
authors.lastname: Zhang
authors.forename: Min
authors.initials: M
authors.lastname: Tang
authors.forename: Keping
authors.initials: K
authors.lastname: Chen
authors.forename: Jielin
authors.initials: J
authors.lastname: Pu
authors.forename: Fangzheng
authors.initials: F
authors.lastname: Wang
authors.forename: Xin
authors.initials: X
authors.lastname: Chen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000628:therapy*; D017115:Catheter Ablation / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged