Venous allografts for vascular reconstructions

In order to evaluate various protocols for the preservation of venous allografts 162 arterial reconstructions were performed in mongrel dogs bypassing their ligated femoral arteries. The cumulative 6-month patency-rates as determined by weekly palpation and regular angiography were. Group I = Synthetic grafts: (a) Dacron 48%, (b) PTFE 53%. Group II = Fresh venous grafts: (a) autografts 100%, (b) allografts 37%. Group III = Veins preserved in saline at 4 degrees C for 1 month: (a) autografts 44%, (b) allografts 34%. Group IV = Veins preserved in saline at -70 degrees C: (a) autografts 58%, (b) allografts 47%. Group V = Veins preserved in glutaraldehyde solution: (a) autografts 26%, (b) allografts 22%. Group VI = Veins preserved in Hanks-solution with 15% DMSO at -160 degrees C: (a) autografts 77%, (b) allografts 35%. Histological as well as immunological studies suggest that these results are determined by the preservation protocol in Groups III, IV and V and by the presence of rejection in Groups I and VI. As the results with the allografts are not superior to those obtained with synthetic grafts, their use should be confined to those cases where the use of synthetic materials should be avoided at any price. Further experiments with immunosuppression and antigenic matching are indicated to see whether this would improve the results obtained with viable venous allografts.