title: Assessing the immediate and sustained effectiveness of circular epicardial surgical ligation of the left atrial appendage.
abstract: OBJECTIVE
  Obliterating the left atrial appendage from systemic circulation in patients with atrial fibrillation has been proposed to reduce thromboembolic events. The goal of this study was to assess the effectiveness of a circular method of epicardial surgical ligation in obliterating the left atrial appendage and maintaining sustained exclusion.
  
  
  METHODS
  Patients with permanent atrial fibrillation and an indication for elective cardiac surgery were enrolled. All patients underwent preoperative cardiac gated computerized tomography (CT) and transesophageal echocardiography (TEE). During the cardiac procedure circular ligation of the appendage was performed.
  
  
  RESULTS
  Twelve patients, mean (SD) age 65 (12) years completed the study. Intraoperative TEE demonstrated all patients (12/12) had complete postligation occlusion of the left atrial appendage. At three-month follow-up, cardiac gated CT demonstrated that 75% (9/12) of the patients had communication of contrast dye from the left atrial appendage to body of left atrium. Left atrial appendage orifice area and volume were reduced from mean (SD) (5.5 cm(2) [1.8] to 0.5 cm(2) [0.4] p = 0.002) and (14.0 cm(3) [8.3] to 2.7 cm(3) [1.3] p = .005) postligation, respectively. No clinically significant thromboembolic events were reported.
  
  
  CONCLUSIONS
  Epicardial suture ligation of the left atrial appendage resulted in successful intra-operative exclusion on TEE; however, a significant portion of patient's demonstrated communication of contrast on CT. This is suggestive of incomplete long-term exclusion. The clinical significance of reduction in left atrial appendage orifice area and volume with a persistent communication requires further study.
authors.affiliation: Division of Cardiac Surgery, Department of Surgery, University of Western Ontario, London Health Sciences Centre, London, Ontario, Canada.
authors.forename: Corey
authors.initials: C
authors.lastname: Adams
authors.forename: Daniel
authors.initials: D
authors.lastname: Bainbridge
authors.forename: Aashish
authors.initials: A
authors.lastname: Goela
authors.forename: Ian
authors.initials: I
authors.lastname: Ross
authors.forename: Bob
authors.initials: B
authors.lastname: Kiaii
mesh_terms: D000368:Aged; D020517:Atrial Appendage / Q000000981:diagnostic imaging / Q000601:surgery*; D001281:Atrial Fibrillation / Q000150:complications / Q000601:surgery*; D055424:Cardiac-Gated Imaging Techniques; D017548:Echocardiography, Transesophageal; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008026:Ligation; D008297:Male; D008875:Middle Aged; D013923:Thromboembolism / Q000209:etiology / Q000517:prevention & control*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome