Objective In order to establish a substitute material of small-caliber vascular graft,an experiment with heterogenic graft transplantation in canine model was carried out.The study was designed to evaluate the safety,reliability of the epoxy treated porcine blood vessels as vascular graft.Methods 17 female dogs were used in this experiment: 10 dogs received the epoxy treated porcine graft(PG),while the other 7 dogs received standard Gortex e-PTFE grafts(e-PTFE).The animal model was established by using the graft materials to make arteriovenous fistulas of the right femoral artery and vein.In order to evaluate the patency,all the grafts were assessed by Doppler ultrasonic examination and angiography.The grafts were taken out and evaluated by histopathological examination after 3 months.Results The grafts were assessed by Doppler ultrasonic examination at 1 and 2 weeks after operation and showed that all vessels kept free circulation of blood.The patency rate was 100%.Angiography was performed at 1 month after operation,the PG group kept patency in 6 dogs(60%),and e-PTFE group in 5 dogs(71.4%).At 3 months after operation,the angiography showed patency in 5 dogs of PG group(62.5%) and 4 dogs in P group(66.7%).The difference of the patency bewteen the two groups was statistically not significant(P>0.05).The transplanted vessels were examined by light and scanning electron microscopy at 3 months after operation.No stenosis of the anastomotic stoma was found and the endothelial cells were found to be with nomal structure.There were no signs of calcification in the graft and surrounding tissues.Conclusion\ This preliminary study demonstrated that the epoxy treated porcine blood vessel(PG) as a heterogenous graft is shown to be reliable.However,much more animal research is needed.