Effect Of Post-operative Chemotherapy On Vascular Graft After Prosthetic Replacement Of The Abdominal Aorta In Canine

Objective: To study the effect of postoperative combined intravenous chemotherapy on the ePTFE vascular grafts in mongrel canine models.Methods: After the infrarenal abdominal aorta was replaced by ePTFE prosthesis graft, twenty-six canine models were randomly divided into chemotherapy group (group Chem, n=13) and control group (group Cont, n=13), according to which the postoperative intravenous combined chemotherapy (5-FU:10mg/kg, cis-platinum:1mg/kg) was administrated or not. The animals were sacrificed and graft specimens were harvested at6weeks (subgroup ChemA and ContA) or14weeks (subgroup ChemB and ContB) after operation. The patency rate of the grafts were observed,and H-E staining of the neointima inside the grafts, immuno-histochemistry test of CD34and PCNA were carried out and analysed.Results:10cases survived in group Chem (10/13,76.9%), while all the dogs in group Cont survived. No evidence of increasing the possibility for blood vessel prosthesis obstruction, infection or anastomotic pseudo-aneurysm was observed, but inflammatory response of the tissues around the grafts was more obvious in group Chem. Small amount of mural thrombus formation were observed in some grafts (ChemA:2/5; ChemB:3/5; ContA:0/6; ContB:2/7). There is no statistical significance about the intima thickness difference between subgroup ContA and ChemA (p>0.05), or between subgroup ContB and ChemB. No statistical difference exists on the coverage of vascular endothelial cells (percentage of CD34+cells) between group Chem and group Cont, except the very middle segment of the grafts in subgroup ContA and ChemA. No statistical difference exists on the PCNA expression between group Chem and Cont (p>0.05). However, in each subgroup, the percentage of CD34+cells and expression of PCNA were the lowest in the middle of the grafts.Conclusions: Postoperative combined intravenous chemotherapy (5-FU and cis-platinum) after prosthetic vessel replacement of abdominal aorta may increase the possibility of mural thrombus formation, and the vascular endothelial cells coverage in the middle of the grafts temporarily as well.It may not significantly influence the patency rate and anastomotic healing of the grafts without increasing the incidence of graft obstruction, infection or anastomotic pseudoaneurysm in12weeks.And it also may not significantly influence the neointimal proliferation or PCNA expression inside the grafts. Further researches are needed for long-term results.