Long-term studies of cold-stored rabbit femoral artery and vein autografts

In previous studies we have shown that 80-100% of rabbit femoral vascular autografts cold-stored at 4 degrees C for 3 weeks remain patent 3 weeks after reinsertion in the femoral artery. The present study reports the effect on graft patency of increasing either the period of cold storage prior to reinsertion or the duration of reperfusion to 6 months. Rabbit femoral blood vessels were cold-stored (CS) at 4 degrees C for varying periods. CS autografts were reinserted into the contralateral leg for 3 weeks or 6 months. Graft patency was determined and grafts examined by histological, immunohistochemical and electron microscopical techniques. Six months after reinsertion patency of 4-week CS arterial and 1-week CS venous grafts was 40% and 27% respectively, very much lower than the 80-100% seen after 3 weeks reperfusion. Arterial grafts CS for 6 months had a patency rate of 70% after 3 weeks reperfusion but 0% after 6 months. Morphological examination suggests that the delayed failure of cold-stored vascular grafts is caused by thrombus superimposed on intimal hyperplasia within the graft. Conclusions: Cold-stored vascular grafts are useful prostheses when only 3-4 weeks graft patency is required. They are not suitable for use when long-term graft patency is needed.