In order to evaluate under what conditions the use of venous homograft
s could yield the best results, 230 arterial reconstructions were perf
ormed in mongrel dogs bypassing their ligated femoral arteries. Cumula
tive 6-month patency-rates were: Group 1: Prosthetic materials: a) Dac
ron grafts: 48%, b) PTFE grafts: 53%. Group 2: Fresh veins: a) autogra
fts: 100%, b) allografts: 37%, c) allografts treated with cyclosporin
4 mg/kg.day for one month: 74% (100% after one month). Group 3: Veins
preserved in saline at 4-degrees-C. for one month: a) autografts: 44%,
b) allograpfts: 34%. Group 4: Frozen veins preserved in saline at -70
-degrees-C for one month: a) autografts: 58%, b) allografts: 47%. Grou
p: 5: Veins preserved in glutaraldehyde 0.25% for one month: a) autogr
afts: 26% b) allografts: 22%. Group 6: Veins preserved in 15% DMSO in
Hanks solution at -160-degrees-C for one month: a) autografts: 77%, b)
allografts: 35%, c) allografts treated with cyclosporin 4 mg/kg.day f
or one month: 72%, d) allografts treated with methylprednisolone 1 mg/
kg.day for one month: 38%, e) allografts treated with cyclosporin 4 mg
/kg and methylprednisolone 1 mg/kg daily for one month: 83%. Fresh vei
ns and veins preserved in 15% DMSO at -160-degrees-C. are viable but i
mmunologically active grafts. In allografts rejection phenomena cause
a relatively high occlusion rate which, however, can be prevented with
low dose cyclosporin. The optimal duration of immunosuppressive thera
py remains to be determined. Veins stored at 4-degrees-C or at -70-deg
rees-C are not viable and only weakly antigenic. Their results are not
better than those obtained with prosthetic material. Glutaraldehyde t
reated veins are non-antigenic and not-viable but their results are wo
rse than with any other method. In combination with low-dose cyclospor
in for a limited period of time viable homologous saphenous veins seem
an acceptable substitute when autologous saphenous vein is not availa
ble. Storage in 15% DMSO at -160-degrees-C can be used for the creatio
n of vein banks which offer the opportunity to have immunologically ma
tched allografts available at any moment.