title: Left atrial appendage exclusion and the risk of thromboembolic events following mitral valve surgery.
abstract: OBJECTIVE
  We aimed to evaluate left atrial appendage (LAA) exclusion in patients undergoing mitral valve surgery with respect to thromboembolic events.
  
  
  BACKGROUND
  LAA is the predominant source of emboli in patients with atrial fibrillation. Prophylactic LAA exclusion at the time of heart surgery has been recommended to reduce the risk of future thromboembolism.
  
  
  METHODS
  An observational cohort of 136 patients undergoing LAA exclusion during mitral valve surgery was identified between May 1993 and November 1998 at our institution.
  
  
  RESULTS
  During a mean follow-up of 3.6 +/- 1.3 years, there were 14 (12.3%) thromboembolic events. Compared with patients who received warfarin upon hospital discharge, there were more thromboembolic events in patients not prescribed warfarin upon hospital discharge (n = 7/67, 10% vs n = 6/40, 15%, respectively). The warfarin status was not known for one patient. The majority of thromboembolic events (n = 10/14, 71%) occurred in those who underwent mitral valve repair.
  
  
  CONCLUSIONS
  In this observational study, patients who undergo LAA exclusion during mitral valve surgery to reduce the risk of thromboembolism have a significant incidence of thromboembolic events, especially when warfarin therapy is not prescribed upon hospital discharge.
authors.affiliation: Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, Ohio 44195, USA.
authors.forename: Soufian T
authors.initials: ST
authors.lastname: Almahameed
authors.forename: Mohammed
authors.initials: M
authors.lastname: Khan
authors.forename: Ryan W
authors.initials: RW
authors.lastname: Zuzek
authors.forename: Nour
authors.initials: N
authors.lastname: Juratli
authors.forename: William A
authors.initials: WA
authors.lastname: Belden
authors.forename: Craig R
authors.initials: CR
authors.lastname: Asher
authors.forename: Gian M
authors.initials: GM
authors.lastname: Novaro
authors.forename: David O
authors.initials: DO
authors.lastname: Martin
authors.forename: Andrea
authors.initials: A
authors.lastname: Natale
mesh_terms: D000925:Anticoagulants / Q000627:therapeutic use; D020517:Atrial Appendage / Q000601:surgery*; D001281:Atrial Fibrillation / Q000453:epidemiology; D001705:Bioprosthesis / Q000706:statistics & numerical data; D015331:Cohort Studies; D015897:Comorbidity; D005260:Female; D005431:Florida / Q000453:epidemiology; D005500:Follow-Up Studies; D006325:Heart Atria; D006349:Heart Valve Diseases / Q000601:surgery*; D006350:Heart Valve Prosthesis / Q000706:statistics & numerical data; D019918:Heart Valve Prosthesis Implantation / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery*; D009820:Ohio / Q000453:epidemiology; D011183:Postoperative Complications / Q000453:epidemiology*; D012307:Risk Factors; D013923:Thromboembolism / Q000188:drug therapy / Q000453:epidemiology*; D014859:Warfarin / Q000627:therapeutic use
chemical_list: D000925:Anticoagulants; D014859:Warfarin