title: Percutaneous tissue-engineered pulmonary valved stent implantation.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the feasibility of percutaneously implanted tissue-engineered valved stents in the ovine pulmonary valve position.
  
  
  METHODS
  Porcine pulmonary heart valves and small intestinal submucosa were obtained from a slaughterhouse, and the intestinal submucosa used to cover the inside of the porcine pulmonary valved stents. Endothelial cells and autologous myofibroblasts were obtained from carotid artery segments of juvenile sheep. After myofibroblast seeding, constructs were placed in a dynamic bioreactor system and were cultured for 16 days. After Endothelial cell seeding, the tissue-engineered valved stents were deployed into the pulmonary valve annular site. Angiography was performed at implantation and explantation (4 weeks). Constructs were analyzed macroscopically and microscopically.
  
  
  RESULTS
  Orthotopic positioning of the stents (n = 3) at the time of implantation and explantation, as well as normal valve function, was observed through angiography. Gross morphology confirmed excellent opening and closing of all leaflets. Strong expression of alpha-smooth muscle actin in neointerstitial cells and of von-Willebrand-Factor in endothelial cells was revealed by immunocytochemistry.
  
  
  CONCLUSIONS
  This study demonstrates successful merging of two novel technologies: (1) percutaneous valved stent implantation and (2) tissue engineering of autologous heart valves.
authors.affiliation: Department of Cardiovascular Surgery, Christian-Albrechts-University of Kiel, School of Medicine, Kiel, Germany. lutter@kielheart.unikiel.de
authors.forename: Georg
authors.initials: G
authors.lastname: Lutter
authors.forename: Anja
authors.initials: A
authors.lastname: Metzner
authors.forename: Thomas
authors.initials: T
authors.lastname: Jahnke
authors.forename: René
authors.initials: R
authors.lastname: Bombien
authors.forename: Jessica
authors.initials: J
authors.lastname: Boldt
authors.forename: Kenji
authors.initials: K
authors.lastname: Iino
authors.forename: Jochen
authors.initials: J
authors.lastname: Cremer
authors.forename: Ulrich A
authors.initials: UA
authors.lastname: Stock
mesh_terms: D000818:Animals; D002339:Carotid Arteries / Q000166:cytology; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000637:transplantation; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D011664:Pulmonary Valve / Q000601:surgery*; D012756:Sheep; D023822:Tissue Engineering / Q000379:methods*; D014182:Transplantation, Autologous