title: Steps toward the percutaneous replacement of atrioventricular valves an experimental study.
abstract: OBJECTIVE
  The goal of this study was to develop a device for percutaneous replacement of the tricuspid valve in animals.
  
  
  BACKGROUND
  Percutaneous valve replacement has recently been introduced, and early clinical experience has been reported. To date, this technique is limited to the replacement of pulmonary and aortic valves in selected patients.
  
  
  METHODS
  A newly designed nitinol stent, forming two large disks separated by a cylinder with a diameter of 18 mm, was specially designed for the purpose of this study. An 18-mm bovine valve was mounted in the central part of the stent, and a polytetrafluoroethylene membrane was sutured onto the ventricular disk. Eight ewes were equally divided into two groups (group 1, acute study; group 2, killed at one month).
  
  
  RESULTS
  Seven of eight devices were successfully delivered in the desired position. In one animal, the device was trapped in tricuspid cordae, leading to its incomplete opening. A significant paravalvular leak was noticed in one animal of group 2. Mean right atrial pressure increased from 5 to 7 mm Hg and did not change during the follow-up. At autopsy, examination confirmed the good position of devices in successfully implanted animals.
  
  
  CONCLUSIONS
  Implantation of a semi-lunar valve in the tricuspid position is possible in ewes through a transcatheter approach. A disk-based nitinol stent is needed to allow valve implantation in the atrioventricular position. These studies open new perspectives into tricuspid as well as mitral valve replacement.
authors: Service de Cardiologie Pédiatrique, Hôpital Necker Enfants Malades, Paris, France. younes.boudjemline@nck.ap-hop-paris.fr
authors: Younes
authors: Y
authors: Boudjemline
authors: Gabriella
authors: G
authors: Agnoletti
authors: Damien
authors: D
authors: Bonnet
authors: Luc
authors: L
authors: Behr
authors: Nicolas
authors: N
authors: Borenstein
authors: Daniel
authors: D
authors: Sidi
authors: Philipp
authors: P
authors: Bonhoeffer
mesh_terms: D000497:Alloys; D000818:Animals; D006328:Cardiac Catheterization; D002417:Cattle; D004452:Echocardiography; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000295:instrumentation / Q000379:methods; D008567:Membranes, Artificial; D011138:Polytetrafluoroethylene; D011474:Prosthesis Design; D012756:Sheep; D015607:Stents; D014261:Tricuspid Valve / Q000601:surgery
chemical_list: D000497:Alloys; D008567:Membranes, Artificial; C013616:nitinol; D011138:Polytetrafluoroethylene