Autogenous connective tissue tubes with “built-in” polyester mesh has been shown to be excellent arterial substitutes (Noishiki, 1976). In the present report, results of observation on healing process around the grafts at an early stage are presented. Examination was carried out over a period from 2 hours to 95 days after implantation of the grafts in the thoracic aortae in 31 canines.
Under the microscope, the grafts were found to be lined initially by a thin layer of mural thrombus, which turned into a layer of fibrin with platalets and leucocytes within 1 day. Fibroblasts were observed in the fibrin layer after 2 days, and capillaries appeared penetrating the layer to connect blood vessels in surrounding tissue and the lumen of the graft after 4 days. One week later, numerous mouths of the capillaries were observed at a number of different places of the graft carrying endothelium. Discrete islands of endothelium were observed at a number of different places over inner surface of the graft two weeks after the implantation. Each island had one or more mouths of blood vessels. The endothelial lining of the inner wall was completed within 10 weeks.
The above observation indicates that the grafts have a high ability of healing and that endothelial lining on the grafts develops not only from the adjacent endothelium of the aorta but also from islands of the endothelium which appear to pass through the layer of fibrin from the connective tissue of the grafts.
