title: In vitro mitral valve simulator mimics systolic valvular function of chronic ischemic mitral regurgitation ovine model.
abstract: BACKGROUND
  This study was undertaken to evaluate an in vitro mitral valve (MV) simulator's ability to mimic the systolic leaflet coaptation, regurgitation, and leaflet mechanics of a healthy ovine model and an ovine model with chronic ischemic mitral regurgitation (IMR).
  
  
  METHODS
  Mitral valve size and geometry of both healthy ovine animals and those with chronic IMR were used to recreate systolic MV function in vitro. A2-P2 coaptation length, coaptation depth, tenting area, anterior leaflet strain, and MR were compared between the animal groups and valves simulated in the bench-top model.
  
  
  RESULTS
  For the control conditions, no differences were observed between the healthy animals and simulator in coaptation length (p = 0.681), coaptation depth (p = 0.559), tenting area (p = 0.199), and anterior leaflet strain in the radial (p = 0.230) and circumferential (p = 0.364) directions. For the chronic IMR conditions, no differences were observed between the models in coaptation length (p = 0.596), coaptation depth (p = 0.621), tenting area (p = 0.879), and anterior leaflet strain in the radial (p = 0.151) and circumferential (p = 0.586) directions. MR was similar between IMR models, with an asymmetrical jet originating from the tethered A3-P3 leaflets.
  
  
  CONCLUSIONS
  This study is the first to demonstrate the effectiveness of an in vitro simulator to emulate the systolic valvular function and mechanics of a healthy ovine model and one with chronic IMR. The in vitro IMR model provides the capability to recreate intermediary and exacerbated levels of annular and subvalvular distortion for which IMR repairs can be simulated. This system provides a realistic and controllable test platform for the development and evaluation of current and future IMR repairs.
authors: The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, USA. ajit.yoganathan@bme.gatech.edu
authors: Andrew W
authors: AW
authors: Siefert
authors: Jean Pierre M
authors: JP
authors: Rabbah
authors: Kevin J
authors: KJ
authors: Koomalsingh
authors: Steven A
authors: SA
authors: Touchton
authors: Neelakantan
authors: N
authors: Saikrishnan
authors: Jeremy R
authors: JR
authors: McGarvey
authors: Robert C
authors: RC
authors: Gorman
authors: Joseph H
authors: JH
authors: Gorman
authors: Ajit P
authors: AP
authors: Yoganathan
mesh_terms: D000818:Animals; D003198:Computer Simulation; D004195:Disease Models, Animal; D008943:Mitral Valve / Q000503:physiopathology*; D008944:Mitral Valve Insufficiency / Q000209:etiology / Q000503:physiopathology*; D017202:Myocardial Ischemia / Q000150:complications* / Q000503:physiopathology; D012720:Severity of Illness Index; D034561:Sheep, Domestic; D013599:Systole; D016277:Ventricular Function, Left / Q000502:physiology*
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