title: Preclinical evaluation of a new left atrial appendage occluder (Lifetech LAmbre™ device) in a canine model.
abstract: OBJECTIVE
  The study evaluated the feasibility and safety of a novel left atrial appendage (LAA) occluder (LAmbre™, Lifetech Scientific Corp., China) in canines.
  
  
  BACKGROUND
  Transcatheter LAA occlusion is comparable to warfarin in preventing atrial fibrillation-related strokes.
  
  
  METHODS
  Twenty-two healthy dogs (28 ± 3 kg) received LAmbre implants. The device is delivered by an 8-10 French sheath and has full recapture and repositioning capabilities. All dogs received 1-week antibiotics and 4-week aspirin (80 mg daily) after implants and they were sacrificed in groups at Days 1-3 (n = 5), 1- (n = 7), 3- (n = 4) and 6-months (n = 6) for pathological examinations. Transthoracic echocardiography (TTE) was performed immediately after implant, at Day 3 and before sacrifice.
  
  
  RESULTS
  The LAmbre was successfully implanted, retrieved, repositioned and re-implanted in all dogs. The mean implant size was 24 ± 3 mm and the device chosen was 36 ± 7% larger than the measured landing zone diameter. Improper device selection (only 21% oversizing) resulted in dislodgement and death of 1 dog on Day 3. Post-implant angiography and TTE showed well-positioned device without pericardial effusion or impingement on surrounding structures. Late complications included device-related thrombus at 1 month (n = 1) and clinically insignificant pericardial effusion at Day 3 (n = 1). Complete healing on the atrial facing surface with optimal LAA obliteration was confirmed by gross and microscopic examinations in dogs that have been followed up ≥3 months (n = 10). No infarct was detected in major organs.
  
  
  CONCLUSIONS
  Our preliminary data suggested the LAmbre™ device is feasible with high success rate in canines. Further studies are needed to evaluate its safety and efficacy.
authors.affiliation: SH Ho Cardiovascular and Stroke Centre, Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong. Electronic address: yylam@cuhk.edu.hk.
authors.forename: Yat-Yin
authors.initials: YY
authors.lastname: Lam
authors.forename: Bryan P
authors.initials: BP
authors.lastname: Yan
authors.forename: Shephal K
authors.initials: SK
authors.lastname: Doshi
authors.forename: Anning
authors.initials: A
authors.lastname: Li
authors.forename: Deyuan
authors.initials: D
authors.lastname: Zhang
authors.forename: Mehmet G
authors.initials: MG
authors.lastname: Kaya
authors.forename: Jai-Wun
authors.initials: JW
authors.lastname: Park
mesh_terms: D000818:Animals; D020517:Atrial Appendage / Q000000981:diagnostic imaging / Q000601:surgery*; D001281:Atrial Fibrillation / Q000000981:diagnostic imaging / Q000517:prevention & control*; D006328:Cardiac Catheterization / Q000379:methods / Q000592:standards*; D004195:Disease Models, Animal; D004285:Dogs; D005500:Follow-Up Studies; D055989:Septal Occluder Device / Q000592:standards*; D014463:Ultrasonography
keywords: Atrial fibrillation; LAmbre; Left atrial appendage occlusion; Stroke