title: Patency of synthetic microvenous conduits: an experimental study in the femoral vein of the rat.
abstract: A temporary arteriovenous fistula was used to enhance the patency of 1.5-mm expanded polytetrafluoroethylene grafts. A segment of polytetrafluoroethylene measuring 5.0 mm in length was interposed into the femoral vein of rats. In the control group (n = 4), no arteriovenous fistula was made and all were thrombosed at 30 minutes. In the experimental group (n = 18), the arteriovenous fistula was ligated after 2 days (n = 8), 14 days (n = 6), or not at all (n = 4). The animals were reexplored 40 to 70 days later, and all the grafts were found to be patent regardless of when the fistula was ligated (patency rate 100 percent). Light and scanning electron microscopy showed complete endothelialization. Presumably the arteriovenous fistula exposes the graft to a high-flow system, allowing a nonthrombogenic pseudointima to form which is later replaced by a true endothelium.
mesh_terms: D000818:Animals; D001166:Arteriovenous Shunt, Surgical; D001807:Blood Vessel Prosthesis; D004727:Endothelium / Q000473:pathology; D005268:Femoral Vein / Q000473:pathology / Q000601:surgery; D006083:Graft Occlusion, Vascular; D008297:Male; D008833:Microcirculation / Q000601:surgery*; D011138:Polytetrafluoroethylene; D051381:Rats
chemical_list: D011138:Polytetrafluoroethylene