The Effect of Post-operative Irradiation with High Dose External Beam Radiation on the Neointima of Vascular Graft after Inferior Vena Cava Prosthetic Vessel Replacement in Canine
|School||Central South University|
|Keywords||Postoperative radiotherapy PCNA CD34 Artificial blood vessels Endometrial|
Objective To observe the high-dose external beam radiation therapy for canine inferior vena cava replacement surgery artificial graft patency, intimal hyperplasia and endothelial cell coverage of the impact. Methods 16 adult mongrel dogs were randomly divided into radiotherapy group and control group 8. Both groups were first surgical intervention. The use of 6mm ePTFE graft inferior vena cava replacement. After 2 weeks of radiotherapy given radiation dose of 35Gy fractionated irradiation in vitro artificial blood vessel itself and the proximal and distal anastomosis; control group only the inferior vena cava replacement surgery, postoperative irradiation treatment not. Respectively, after 8 weeks to collect specimens, animals were observed inferior vena cava graft patency, and through HE staining and immunohistochemical method of postoperative radiotherapy on artificial graft intimal hyperplasia and vascular endothelial cell coverage effects. Results 1 two groups of dogs were alive. 2 radiotherapy group of eight patients and a control group of six cases of artificial blood flow unobstructed. Control group, 2 patients had graft anastomosis healed. Radiotherapy group graft patency rate of 8/8; control group patency rate was 6/8. 3.HE staining found eight cases radiotherapy group and the control group were six cases of artificial blood vessels form a complete lining. 4 artificial intimal thickness measurement results are shown: the proximal, middle, distal end of each segment radiotherapy group (610.69 ± 32.90μm, 530.51 ± 32.14μm, 544.52 ± 41.99μm) of endometrial thickness than the respective control group ( 753.39 ± 10.36μm, 636.55 ± 20.23μm, 710.39 ± 30.92μm) endometrial thickness was significantly decreased (P <0.01). Control group, the middle graft intimal thickness (636.55 ± 20.23μm) closer to the heart side intima-media thickness (753.39 ± 10.36μm) decreased significantly (P <0.01). 5 radiotherapy group percentage PCNA-positive cells in the proximal graft (45.1% ± 7.5%) than that of the control group (56.3% ± 7.8%) was significantly lower (P <0.01). In the radiotherapy group, the middle of PCNA-positive cells graft percentage (29.5% ± 4.3%) and its proximal percentage of PCNA-positive cells (45.1% ± 7.5%) was significantly lower in comparison (P <0.01). In the control group, the distal end of the graft percentage of PCNA-positive cells (38.9% ± 8.1%) close to the heart side (56.3% ± 7.8%) was significantly lower (P <0.01); artificial vascular middle of PCNA-positive cell percentage (34.9 % ± 6.5%) close to the heart side (56.3% ± 7.8%) was significantly lower (P <0.01). 6 between the radiotherapy group and the control group artificial intimal vascular endothelial cell coverage was no significant difference. Conclusion 1 short-term observation (6 weeks after irradiation) postoperative radiotherapy (35Gy) does not cause vein graft anastomosis do not heal, cracked and bleeding. 2 postoperative radiotherapy (35Gy) does not reduce vein graft patency segment. 3 postoperative radiotherapy (35Gy) for postoperative venous graft replacement graft neointimal formation and PCNA expression was inhibited. 4 graft replacement after giving 35Gy external radiotherapy, artificial intimal coverage of endothelial cells had no significant effect.