title: Left atrial appendage occlusion for prevention of stroke in nonvalvular atrial fibrillation: a meta-analysis.
abstract: OBJECTIVE
  When anticoagulation for stroke prevention is contraindicated, left atrial appendage occlusion (LAAO) may be performed. Studies of LAAO have been limited by their small size, disparate patient populations, and lack of control group. Our purpose was to perform a meta-analysis of the safety and efficacy of LAAO in comparison with standard therapy for stroke prevention in nonvalvular AF.
  
  
  METHODS
  Due to the lack of a control group in studies of LAAO, data on stroke prevention from multiple large outcomes studies were used to produce a hypothetical control group based on clinical variables in the individual studies. Results were stratified according to LAAO device type.
  
  
  RESULTS
  We identified 16 studies with a total of 1759 patients receiving LAAO. Summary estimates demonstrate LAAO reduced risk of stroke in comparison with no therapy or aspirin therapy [relative risk (RR), 0.34; 95 % CI, 0.25-0.46] and in comparison with warfarin therapy (RR, 0.65; 95 % CI, 0.46-0.91). Summary estimates differed based on the study used to derive the hypothetical control group. Device deployment was unsuccessful in 6.1 % of patients, and overall complication rate was 7.1 %. Efficacy and safety were similar across LAAO device type although a majority of patients in the meta-analysis received a Watchman device.
  
  
  CONCLUSIONS
  Our data suggest that LAAO is a reasonable option for stroke prophylaxis in AF when anticoagulation is not an option, and the risk for stroke outweighs the risk of procedural complications. Data were limited with the use of most available devices. To better establish the risk and benefit of LAAO in comparison with standard therapy, more randomized controlled trials are necessary.
authors.affiliation: Cardiac Electrophysiology, Division of Cardiology, CB 7075, 160 Dental Circle, 6025 Burnett-Womack Bldg, Chapel Hill, NC, 27599-7075, USA.
authors.forename: Weeranun D
authors.initials: WD
authors.lastname: Bode
authors.forename: Nikhil
authors.initials: N
authors.lastname: Patel
authors.forename: Anil K
authors.initials: AK
authors.lastname: Gehi
mesh_terms: D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use*; D020517:Atrial Appendage / Q000601:surgery; D001281:Atrial Fibrillation / Q000401:mortality* / Q000628:therapy*; D015984:Causality; D015897:Comorbidity; D005260:Female; D006349:Heart Valve Diseases / Q000401:mortality; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D020521:Stroke / Q000401:mortality* / Q000517:prevention & control*; D015996:Survival Rate; D060205:Therapeutic Occlusion / Q000401:mortality / Q000706:statistics & numerical data*; D016896:Treatment Outcome
chemical_list: D000925:Anticoagulants