title: Development of left ventricular hypertrophy in a novel porcine model of mitral regurgitation.
abstract: OBJECTIVE
  We aimed to develop a porcine model for chronic nonischemic mitral regurgitation (MR) to investigate left ventricular (LV) enlargement and eccentric hypertrophy.
  
  
  METHODS
  Nonischemic MR was induced in 30 pigs by open-chest immobilization of the posterior mitral leaflet by transannular traction sutures that where applied in transmyocardial fashion. A sham operated control group (n = 13) was included. Echocardiographic LV size and heart weight assessed at euthanasia were used to evaluate the development of LV enlargement and eccentric hypertrophy after 8 weeks follow-up.
  
  
  RESULTS
  Eight pigs died and seven were excluded due to mediastinal infection (n = 2) or failure to produce MR (n = 5). Thus, 28 pigs were included and were divided into three groups: controls (n = 12), mild MR (mMR; n = 10), and moderate to severe MR (sMR; n = 6). The change in LV internal diameter in diastole (LVIDd) from baseline to follow-up was significantly higher in the sMR group compared to that of the control group (P = 0.0017). Furthermore, LV weight was significantly increased in the mMR (P = 0.047) and the sMR (P = 0.0087) groups compared to that of the control group.
  
  
  CONCLUSIONS
  A new model for chronic moderate to severe nonischemic MR with development of LV enlargement and eccentric hypertrophy within 8 weeks has been established in pigs.
authors.affiliation: Department of Cardiothoracic and Vascular Surgery, Aarhus University Hospital , Skejby, Aarhus , Denmark.
authors.forename: Nathja
authors.initials: N
authors.lastname: Ravn
authors.forename: Nora E
authors.initials: NE
authors.lastname: Zois
authors.forename: Sophia G
authors.initials: SG
authors.lastname: Moesgaard
authors.forename: Jesper L
authors.initials: JL
authors.lastname: Honge
authors.forename: Morten H
authors.initials: MH
authors.lastname: Smerup
authors.forename: J Michael
authors.initials: JM
authors.lastname: Hasenkam
authors.forename: Erik
authors.initials: E
authors.lastname: Sloth
authors.forename: Signe E
authors.initials: SE
authors.lastname: Cremer
authors.forename: Lisbeth H
authors.initials: LH
authors.lastname: Olsen
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D017379:Hypertrophy, Left Ventricular / Q000209:etiology*; D008944:Mitral Valve Insufficiency / Q000150:complications*; D013552:Swine
keywords: animal model; experimental; left ventricular hypertrophy; left ventricular remodeling; mitral valve incompetence