Immediate and long-term evolution of the blood-venous graft interface. Experimental study in dogs

Endothelial damage and repair in autogenous saphenous vein grafts was evaluated serially from 30 s to 9 months after implantation into the femoral arteries of 25 dogs. Light and scanning electron microscopy, quantitative morphometry and cytochemistry with specific rabbit antidog factor VIII-related antigen were used. These studies demonstrate: (1) early complete endothelial cell desquamation both on the venous graft and adjacent artery apparently related to dissection and suture; (2) differing early platelet activation on the venous and adjacent arterial wall, platelet aggregates were noted on the adjacent artery, whereas only adhesive platelets are noted on the exposed vein graft; (3) endothelial reconstitution being initiated after 10-15 days but not reaching completion even 9 months after implantation; (4) a mediointimal proliferation which is a constant feature. A unique cell possessing both fibroblastic and myocytic characteristics takes part in the process.