title: Transcatheter valve insertion in a model of enlarged right ventricular outflow tracts.
abstract: OBJECTIVE
  Transcatheter pulmonary valve insertion has recently emerged as an alternative to surgery. To extend its indications to patients with a large right ventricular outflow tract, we previously developed an intravascular device that reduces the diameter of the main pulmonary artery, allowing the insertion of available valved stents. Here we report its use in a model of animals with an enlarged right ventricular outflow tract and pulmonary valve incompetence.
  
  
  RESULTS
  The study comprised 33 sheep that first underwent surgical enlargement of the main pulmonary artery. We then intended to implant a filler percutaneously, followed later by the insertion of a valve. Three animals died during the intermediate stage. The remainder were humanely killed either immediately (group 1, n = 6) or after a mean follow-up of 1 (group 2, n = 12) or 2 months (group 3, n = 12). Animals from groups 2 and 3 were equally divided into 2 subgroups according to the difference between diameters of the device inserted and the main pulmonary artery (A < 5 mm, B > or = 5 mm). Fillers were all inserted successfully (n = 30), although one embolized after its insertion (group 3A). A valved stent was implanted in all animals, but in 1 case a balloon ruptured during inflation of the stent leading to incomplete expansion and the death of the animal. Six animals, 5 of which were from group A, had pulmonary regurgitation after valve insertion.
  
  
  CONCLUSIONS
  Pulmonary valve insertion is possible through a transcatheter technique using a pulmonary artery filler. Oversizing the device reduces the risk of embolization and paraprosthetic leak.
authors.affiliation: Service de Cardiologie Pédiatrie, Hôpital Necker-Enfants Malades, Assistance Publique Hôpitaux de Paris, France.
authors.forename: Adeline
authors.initials: A
authors.lastname: Basquin
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Pineau
authors.forename: Louise
authors.initials: L
authors.lastname: Galmiche
authors.forename: Damien
authors.initials: D
authors.lastname: Bonnet
authors.forename: Daniel
authors.initials: D
authors.lastname: Sidi
authors.forename: Younes
authors.initials: Y
authors.lastname: Boudjemline
mesh_terms: D000818:Animals; D002404:Catheterization; D004195:Disease Models, Animal; D006350:Heart Valve Prosthesis; D019919:Prosthesis Implantation / Q000379:methods*; D011651:Pulmonary Artery / Q000473:pathology*; D011665:Pulmonary Valve Insufficiency / Q000628:therapy; D012756:Sheep; D015607:Stents