title: Percutaneous pulmonary valve replacement using completely tissue-engineered off-the-shelf heart valves: six-month in vivo functionality and matrix remodelling in sheep.
abstract: OBJECTIVE
  The objective was to implant a stented decellularised tissue-engineered heart valve (sdTEHV) percutaneously in an animal model, to assess its in vivo functionality and to examine the repopulation and remodelling of the valvular matrix by the recipient's autologous cells.
  
  
  RESULTS
  Prototypes of sdTEHV were cultured in vitro, decellularised and percutaneously implanted into the pulmonary position in 15 sheep. Functionality was assessed monthly by intracardiac echocardiography (ICE). Valves were explanted after eight, 16 or 24 weeks and analysed macroscopically, histologically and by electron microscopy. Implantation was successful in all animals. Valves showed normal pressure gradients throughout the study. Due to a suboptimal design with small coaptation area, stent ovality led to immediate regurgitation which continuously increased during follow-up. Analyses revealed complete endothelialisation and rapid cellular repopulation and remodelling of the entire matrix. Valves were free from endocarditis, calcification and graft rejection.
  
  
  CONCLUSIONS
  sdTEHV can be safely implanted percutaneously. The fast autologous recellularisation and the extensive matrix remodelling demonstrate the valve's potential as a next-generation percutaneous prosthesis with the capacity for tissue self-maintenance and longevity. Regurgitation may be prevented by valve design optimisation.
authors.affiliation: Department of Congenital Heart Disease and Paediatric Cardiology, Deutsches Herzzentrum Berlin, Berlin, Germany.
authors.forename: Boris
authors.initials: B
authors.lastname: Schmitt
authors.forename: Hendrik
authors.initials: H
authors.lastname: Spriestersbach
authors.forename: Darach
authors.initials: D
authors.lastname: O H-Icí
authors.forename: Torben
authors.initials: T
authors.lastname: Radtke
authors.forename: Marco
authors.initials: M
authors.lastname: Bartosch
authors.forename: Heiner
authors.initials: H
authors.lastname: Peters
authors.forename: Matthias
authors.initials: M
authors.lastname: Sigler
authors.forename: Laura
authors.initials: L
authors.lastname: Frese
authors.forename: Petra E
authors.initials: PE
authors.lastname: Dijkman
authors.forename: Frank P T
authors.initials: FP
authors.lastname: Baaijens
authors.forename: Simon P
authors.initials: SP
authors.lastname: Hoerstrup
authors.forename: Felix
authors.initials: F
authors.lastname: Berger
mesh_terms: D000818:Animals; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000379:methods; D006351:Heart Valves / Q000601:surgery*; D023421:Models, Animal; D011664:Pulmonary Valve / Q000503:physiopathology / Q000601:surgery*; D012756:Sheep; D013997:Time Factors; D023822:Tissue Engineering