title: Beating-heart, off-pump mitral valve repair by implantation of artificial chordae tendineae: an acute in vivo animal study.
abstract: OBJECTIVE
  To evaluate the effectiveness of a new off-pump mitral valve repair technology in restoring valve competency in a porcine model of acute mitral regurgitation.
  
  
  METHODS
  Acute mitral regurgitation was induced in 6 anesthetized pigs by cutting anterior leaflet chordae. Artificial chordae were then transapically implanted on the prolapsing segment under epicardial echocardiographic guidance and secured outside the left ventricular apex. All intracardiac manipulations were performed off-pump, through a stab wound incision on the left ventricular apex.
  
  
  RESULTS
  Cutting the anterior leaflet chordae caused an eccentric, posteriorly directed jet of mitral regurgitation that could be visualized by color Doppler sonography. Implantation of chordae through the left ventricular apex completely eliminated valve regurgitation in 4 animals and reduced regurgitation in 2. Intraoperative measurement of artificial chordal tensions gave similar values to those reported for native chordae.
  
  
  CONCLUSIONS
  Off-pump, transapical implantation of artificial chordae between a prolapsing anterior mitral valve leaflet and the left ventricular apex was effective in reducing acutely induced mitral regurgitation. Long-term studies are planned to assess the stability in this animal model.
authors.affiliation: Division of Cardiothoracic Surgery, Heart, Lung and Esophageal Surgery Institute, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA.
authors.forename: Pietro
authors.initials: P
authors.lastname: Bajona
authors.forename: William E
authors.initials: WE
authors.lastname: Katz
authors.forename: Richard C
authors.initials: RC
authors.lastname: Daly
authors.forename: Kenton J
authors.initials: KJ
authors.lastname: Zehr
authors.forename: Giovanni
authors.initials: G
authors.lastname: Speziali
mesh_terms: D000818:Animals; D002815:Chordae Tendineae; D004195:Disease Models, Animal; D004867:Equipment Design; D005240:Feasibility Studies; D005336:Fiber Optic Technology / Q000295:instrumentation; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D008943:Mitral Valve / Q000601:surgery*; D008944:Mitral Valve Insufficiency / Q000601:surgery*; D013552:Swine