title: Comparison of the ovine and porcine animal models for biocompatibility testing of vascular prostheses.
abstract: OBJECTIVE
  Evaluation of the pig and sheep models for biocompatibility investigations of vascular prostheses (VP).
  
  
  METHODS
  Comparative analysis of animal experimental investigations involving two different animal models.
  
  
  METHODS
  Commercially available polyester vascular prostheses (PET-VP) were implanted into two different animal models (infrarenal porcine aorta and ovine carotid artery). The costs, surgical handling, patency rate, and healing on the basis of macroscopic, microscopic, and immunohistochemical criteria were analyzed over a period of 3 months.
  
  
  RESULTS
  Handling and operating times (63 +/- 10 versus 76 +/- 16 min; P = 0.125) did not differ significantly. The cost of the two animal models was comparable. Integration of the VP was complete in the sheep model, but varied in the pig model (two complete, four incomplete). Complete endothelialization of all VPs was observed in the pig, which contrasted with the sheep with complete (circular) endothelialization only in the region of the anastomosis. The thickness of neointima in the region of the anastomosis differed insignificantly; immunohistochemically, only periprosthetic Ki67 was significantly reduced (28.7 +/- 9.9 versus 6 +/- 0.9%; P = 0.002) in the sheep.
  
  
  CONCLUSIONS
  In the porcine model, extremely good endothelialization of the VP was observed, with formation of a rapid neointimal hyperplasia. The ovine model was characterized by the fact that postoperative follow-up investigations were easy to perform. Complete endothelialization was not observed.
authors.affiliation: Freidrich-Schiller-University, Department of Cardiothoracic and Vascular Surgery, Erlanger Allee 101, 07747 Jena, Germany. ueberrueck@aol.com
authors.forename: Torsten
authors.initials: T
authors.lastname: Ueberrueck
authors.forename: Joerg
authors.initials: J
authors.lastname: Tautenhahn
authors.forename: Lutz
authors.initials: L
authors.lastname: Meyer
authors.forename: Olaf
authors.initials: O
authors.lastname: Kaufmann
authors.forename: Hans
authors.initials: H
authors.lastname: Lippert
authors.forename: Ingo
authors.initials: I
authors.lastname: Gastinger
authors.forename: Thorsten
authors.initials: T
authors.lastname: Wahlers
mesh_terms: D000818:Animals; D001012:Aorta, Abdominal / Q000473:pathology / Q000601:surgery / Q000648:ultrastructure; D001807:Blood Vessel Prosthesis / Q000191:economics; D002339:Carotid Arteries / Q000473:pathology / Q000601:surgery / Q000648:ultrastructure; D003365:Costs and Cost Analysis; D006965:Hyperplasia; D008422:Materials Testing / Q000191:economics / Q000379:methods*; D023421:Models, Animal; D011091:Polyesters; D019919:Prosthesis Implantation; D012756:Sheep; D034421:Sus scrofa
chemical_list: D011091:Polyesters