title: The feasibility and efficacy of a large-sized lasso catheter combined with 3 dimensional mapping system for catheter ablation of atrial fibrillation.
abstract: OBJECTIVE
  We aimed to investigate whether a large-sized Lasso catheter could increase the success rate of immediate complete pulmonary vein (PV) antral isolation and improve the outcome of catheter ablation in atrial fibrillation (AF) patients.
  
  
  METHODS
  This study included 107 consecutive patients (67 males, mean age: 57.8±9.7 years) who underwent PV mapping and ablation due to symptomatic drug-refractory AF. The first 43 patients underwent isolation of both ipsilateral PVs using the Carto-Merge 3 dimensional mapping system (group 1). The other 64 patients underwent isolation of both ipsilateral PVs using the same technique with a large-sized (a diameter of 30 to 35 mm) Lasso cathe-ter (group 2). When ipsilateral PVs did not show any potential after the initial circumferential ablation, we defined this as 'immediate complete antral isolation (ICAI)'. We compared the AF recurrence rate of both groups.
  
  
  RESULTS
  There was no significant difference of the clinical characteristics between group 1 and group 2. All the patients were followed-up for 1 year. The ICAI rate of group 1 and group 2 was significantly different (21% vs. 78%, p<0.001), and the AF recurrence rates of group 1 and group 2 were also different (34.9% vs. 18.8%, p=0.042). Using multiple logistic regression analysis, the use of a large-sized Lasso catheter was a significant predictive factor for preventing recurrence (odds ratio: 0.489, 95% confidence interval: 0.136-0.927).
  
  
  CONCLUSIONS
  It is likely that a large-sized Lasso catheter plays an important role in achieving ICAI and in lowering the rate of AF recurrence.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, The Catholic University of Korea College of Medicine, Seoul, Korea.
authors.forename: Sung-Won
authors.initials: SW
authors.lastname: Jang
authors.forename: Woo-Seung
authors.initials: WS
authors.lastname: Shin
authors.forename: Ji-Hoon
authors.initials: JH
authors.lastname: Kim
authors.forename: Min-Seok
authors.initials: MS
authors.lastname: Choi
authors.forename: Yun Seok
authors.initials: YS
authors.lastname: Choi
authors.forename: Yong-Seog
authors.initials: YS
authors.lastname: Oh
authors.forename: Man-Young
authors.initials: MY
authors.lastname: Lee
authors.forename: Tai-Ho
authors.initials: TH
authors.lastname: Rho