title: Efficacy of linear block at the left atrial roof in atrial fibrillation.
abstract: BACKGROUND
  After extensive encircling of ipsilateral pulmonary vein isolation (EEPVI) for atrial fibrillation (AF), we sometimes observe AF recurrence, or the occurrence of atrial tachycardia originating from the left atrium. This study examined the efficacy of additional linear ablation at the left atrial (LA) roof in combination with EEPVI to prevent arrhythmia recurrences.
  
  
  METHODS
  This study included 104 patients with drug-refractory AF (75 with paroxysmal, 29 with persistent). The patients in Group A (n=70) underwent EEPVI treatment alone, and the patients in Group B (n=34) underwent linear ablation at the LA roof in addition to EEPVI treatment. At 1, 3, 6, and 12 months after ablation, patients underwent clinical review and 24-h ambulatory electrocardiogram monitoring to identify asymptomatic arrhythmias. Follow-up included daily trans-telephonic event monitoring, transmitted irrespective of the patient's symptoms.
  
  
  RESULTS
  At 12 months, 57% of Group A and 79% of Group B were free of arrhythmias (p<0.05). Cox regression analysis demonstrated that among the variables of age, sex, duration of AF, types of AF (paroxysmal or persistent), LA size, ejection fraction, existence of hypertension, ischemic heart disease, valvular heart disease, history of stroke, and the ablation technique, only the ablation technique of the linear block at the LA roof was the independent predictor of arrhythmia-free recovery after ablation.
  
  
  CONCLUSIONS
  EEPVI in combination with the linear ablation at the LA roof is associated with an improved clinical outcome compared with EEPVI alone.
authors.affiliation: Department of Cardiology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507, Japan.
authors.forename: Michiharu
authors.initials: M
authors.lastname: Senga
authors.forename: Eitaro
authors.initials: E
authors.lastname: Fujii
authors.forename: Shinya
authors.initials: S
authors.lastname: Sugiura
authors.forename: Shoichiro
authors.initials: S
authors.lastname: Yamazato
authors.forename: Emiyo
authors.initials: E
authors.lastname: Sugiura
authors.forename: Mashio
authors.initials: M
authors.lastname: Nakamura
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Miyahara
authors.forename: Masaaki
authors.initials: M
authors.lastname: Ito
mesh_terms: D055011:Ablation Techniques; D001281:Atrial Fibrillation / Q000517:prevention & control / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods; D005260:Female; D006325:Heart Atria; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000601:surgery*; D012008:Recurrence; D016896:Treatment Outcome