Pseudointima in expanded polytetrafluoroethylene graft implanted in the inferior vena cava of normal and defibrinogenated dogs.

Abstract

The pseudointimal formation in an expanded polytetrafluoroethylene graft implanted in the canine inferior vena cava was studied by light and transmission electron microscopy. Five of 6 grafts in the control group and all of the 10 grafts in the batroxobin-defibrinogenated group were patent, and provided for the investigation. The thickness of the mural thrombus formed within 3 days was significantly decreased in the severely defibrinogenated dogs, in which the fibrinogen concentration was below 0.40 gm/L, as compared to the controls and the moderately defibrinogenated dogs, in which the fibrinogen concentration was at highest 0.72-0.87 gm/L. In spite of reducing the fibrinogen concentration to unmeasurable levels after 3 days, there was no obvious difference in the process of pseudointimal formation between the moderately defibrinogenated dogs and the controls. In the severely defibrinogenated dogs, loose and spongoid mural thrombus required a longer time to be reorganized.