title: Development of a growing rat model for the in vivo assessment of engineered aortic conduits.
abstract: BACKGROUND
  Numerous limitations of aortic valve grafts currently used in pediatric patients cause the need for alternative prostheses. For the purpose of in vivo evaluation of novel engineered aortic conduit grafts, we aimed at downsizing a previously described model to create a growing rodent model.
  
  
  METHODS
  U-shaped aortic conduits were sutured to the infrarenal aorta of young Wistar rats (70-80 g, n = 10) in an end-to-side manner. Functional assessment was performed by Doppler sonography and high resolution rodent MRI. Histology and immunohistochemistry followed after 8 wk.
  
  
  RESULTS
  Postoperative recovery rate was 80%. Conforming to clinical observations, postoperative MRI (d 5) and Doppler sonography (wk 8) revealed unimpaired conduit perfusion. Explanted implants were luminally completely covered by an endothelial cell layer with local hyperplasia and accumulation of α-smooth muscle actin (+) cells. Moreover microcalcification of the decellularized scaffolds was observed.
  
  
  CONCLUSIONS
  Our downsized model of aortic conduit transplantation enables overall characterization with detailed analysis of maturation of engineered aortic grafts in a growing organism.
authors.affiliation: Clinic for Cardiovascular Surgery, Heinrich Heine University Medical School, Duesseldorf, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Assmann
authors.forename: Payam
authors.initials: P
authors.lastname: Akhyari
authors.forename: Christofer
authors.initials: C
authors.lastname: Delfs
authors.forename: Ulrich
authors.initials: U
authors.lastname: Flögel
authors.forename: Christoph
authors.initials: C
authors.lastname: Jacoby
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kamiya
authors.forename: Artur
authors.initials: A
authors.lastname: Lichtenberg
mesh_terms: D000367:Age Factors; D000818:Animals; D001012:Aorta, Abdominal / Q000000981:diagnostic imaging / Q000254:growth & development / Q000601:surgery; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging / Q000254:growth & development / Q000637:transplantation*; D001021:Aortic Valve / Q000000981:diagnostic imaging / Q000254:growth & development / Q000637:transplantation*; D001835:Body Weight; D006085:Graft Survival; D008279:Magnetic Resonance Imaging; D023421:Models, Animal; D009929:Organ Size; D051381:Rats; D017208:Rats, Wistar; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds; D020858:Tissue and Organ Harvesting / Q000379:methods; D014184:Transplantation, Homologous; D018608:Ultrasonography, Doppler