title: Improved healing of small-caliber polytetrafluoroethylene prostheses by induction of a clot layer: a review of experimental studies in rats.
abstract: This report reviews our experiments that have been undertaken to test the hypothesis whether the induction of a clot layer on the graft surface of small-caliber polytetrafluoroethylene (PTFE) prostheses might improve their healing. PTFE prostheses with a fibril length of 30 microns, PTFE prostheses with a fibril length of 30 microns and either impregnated with Chitosan, or pretreated with alcohol or mechanically roughened, and PTFE prostheses with a fibril length of 60 microns (all prostheses: length 1 cm, ID 1.5 mm) were implanted into the abdominal aorta of rats and were evaluated from 1 day up till 6 weeks after implantation with regard to the presence or absence of a clot layer and with regard to the amount of graft healing. All untreated PTFE prostheses were never found to be covered with a clot layer and showed poor neoendothelial healing: even at 6 weeks after implantation, there were only endothelial cells near the anastomotic sides, directly on the graft surface. In contrast, all other PTFE prostheses were completely covered with a clot layer upon implantation and demonstrated almost complete neoendothelial healing after 6 weeks. Moreover, in these prostheses, the endothelial cells were present on a matrix of smooth muscle cells. These results confirm our hypothesis that the induction of a clot layer on the graft surface of PTFE prostheses improves their healing: the clot probably functions as a provisional matrix for the regeneration of arterial wall tissue, just as occurs in normal arterial wall repair.
authors.affiliation: Department of Plastic and Reconstructive Surgery, University Hospital of Groningen, The Netherlands.
authors.forename: B
authors.initials: B
authors.lastname: Van der Lei
authors.forename: J W
authors.initials: JW
authors.lastname: Stronck
authors.forename: C R
authors.initials: CR
authors.lastname: Wildevuur
mesh_terms: D000818:Animals; D001777:Blood Coagulation; D001807:Blood Vessel Prosthesis; D008297:Male; D008855:Microscopy, Electron, Scanning; D011138:Polytetrafluoroethylene; D051381:Rats; D011919:Rats, Inbred Strains; D014654:Vascular Patency; D014945:Wound Healing
chemical_list: D011138:Polytetrafluoroethylene