In order to investigate the effect of vascular beds on the vascular wall of autogenously grafted vein, femoral veins were reversely placed in between the cut ends of collateral femoral arteries in 11 dogs with atraumatic technique. The grafted veins were covered with vivid muscle or skin respectively after being assured to be patent, and investigated by histomorphologic method and computerized image analysis technique at postoperative intervals of 1 week, 4 weeks and 16 weeks. The results showed that: 1. One graft developed pseudoaneurysm at 1 week, and two grafts were occulded in skin-covered group, whereas, no complications occurred in muscle-covered group. 2. Intimal thickening of grafts in skin-covered group was much more obvious than that in the muscle-covered group (P lt; 0.05). 3. The relative contents of microstructural components of the graft wall showed no significant difference quantitatively between the two groups. So, the conclusion was: 1. Subcutaneous transplantation appeared to be a potential causative factor in inducing short-term excessive dilatation and long-term intimal hyperplasia of vein graft. 2. Muscular covering is of priority in blood vessel graft.
ObjectiveTo evaluate the effect of human heme oxygenase 1 augmentation in vein grafts by adenoviral mediated gene transfer of heme oxygenase 1 (Ad hHO 1) on intimal hyperplasia.MethodsTwenty one Japanese white rabbits were divided into three groups: control group, Ad null control group, and Ad hHO 1 group(each group 7 rabbits). During the operation of rabbits jugular vein into carotid artery interposition grafting, harvested rabbit jugular vein segments were exposed for 30min at room temperature to heparin saline, recombinant replication deficient adenovirus encoding hHO 1(Ad hHO 1, 1× 10 9pfu/ml), and nude recombinant replication deficient adenovirus (Ad null, 1×10 9pfu/ml). Quantitative histological studies of the vein segments were performed 28 days after operation. Protein of hHO 1 was detected with method of immunohistochemical staining(S P) in 14 days and 28 days after operation.ResultsThe average intimal thickness, medial thickness and intimal to medial(I/M) ratio were calculated for each group 28 days after bypass operation. Compared to intimal thickness, I/M ratio of control group veins and Ad null group veins,Ad hHO 1 group veins decreased significantly( P lt;0.01). There was no statistically difference in medial thickness ( P gt;0 05). Strong staining of hHO 1 was detected in vein grafts wall of Ad hHO 1 group.ConclusionAd hHO 1 gene therapy may inhibit intimal hyperplasia of vein grafts in rabbits.
ObjectiveTo assess the effects of Radix Salviae Miltiorrhizae (RSM) on patency and proliferation lesion of autologous vein to artery grafts in the earlymiddle stage.MethodsAutologous jugular vein was grafted into abdominal artery in the rats. The rats were divided into two groups: RSM group and control group. The rats in RSM group were fed with RSM [24 g/(kg·d )],which began 1 day before operation and continued until harvesting. Vein grafts were harvested at 1,3 days, 1, 2, 4 and 8 weeks after surgery for examining the patency, thickness of intimamedia and expression of proliferating cell nuclear antigen (PCNA). ResultsNo significant differences existed in patency of vein grafts between the two groups (Pgt;0.05). The intimamedia thickness of the vein grafts in RSM group decreased 1/3 compared with control group at 2, 4 and 8 weeks (P<0.01). The PCNA positive cells in RSM group reduced significantly as compared to the control group (P<0.01). ConclusionRSM can inhibit proliferation lesion of vein grafts but has no influence on patency of vein grafts in the earlymiddle stage.
Objective To investigate the results and applicationvalue of crotch-shaped vein grafts in repairing defects of the vessels with a large diameter.Methods From June 1998 to October 2003, 35 cases of vesseldefects with a large diameter were repaired with crotch-shaped vein graft (29 males and 6 females,aged 18 to 45 years with an average of 25.7 years ). The locations of defects were femoral artery in 25 cases, popliteal artery in 2 cases, femoral vein in 7 cases, and subclavian vein in 1 case. The interval between injure and operatioinwas 1-8.5 hours (4.1 hours on average).The blood flows of trouble and healthy vascular were determined with Doppler detector and compared preoperatively andpostoperatively. Results All the anastomotic stomas were patent in 35 cases. Thirty-one cases were followed up 6 weeks to 24 months (9.5 months on average), the patent rate was 100%, no case occurred vasospasm or tromboembolism; 2 cases occurred stomal leak and became hematoma, 3 cases occurred muscular necrosis, and the 5 cases achieved primary healing after secondary operation. The Doppler results showed that there was statistically significant difference in the blood flow betweenpostoperation and preoperation (Plt;0.01), but no statistically significant difference when compared the trouble vascular after operation with healthy vascular (Pgt;0.05). Conclusion The methodof crotch-shaped vein grafts is safe and effective in repairing defects of vessels with a large diameter,which is easy to draw materials and handy to operate. It has a promising value in clinical application.
Objective To assess the effect of topical appl ication of 5-fluorouracil (5-FU) on intimal hyperplasia in rabbit vein graft. Methods Sixty-four male New Zealand white rabbits, aged 5 months and weighing 2.8-3.0 kg, were randomly divided into group A, B, C, and D (n=16 rabbits per group). Artery defect model was establ ished by cutting about 1 cm artery from the middle part of the dissociated left common carotid artery. A section about 3 cm was cut from the right external jugular vein, and the harvested vein was inverted and end-to-end anastomosed to the artery defect with 9-0 non-traumatic suture. After anastomosis, the extima of the grafted veins in group A, B, and C was completely wrapped with cotton sheet (12 mm × 30 mm × 1 mm in size) immersed by 5-FU at a concentration of 50.0, 25.0, and 12.5 mg/mL, respectively, and eachvein was treated 5 times (1 minute at a time). In group D, the extima of the graft veins was treated with normal sal ine instead of 5-FU. The grafted veins were obtained 1, 2, 4, and 6 weeks after operation, HE staining and Masson staining were preformed for histological changes of grafted vein wall, prol iferating cell nuclear antigen (PCNA) immunohistochemistry staining and TUNEL label ing staining were conducted for prol iferation and apoptosis of smooth muscle cell of the grafted vein, and transmission electron microscope observation was performed for cellular ultrastructure. Results The HE staining, Masson staining, and PCNA immunohistochemistry staining showed that the thickness of intima in group A and B was obviously less than that in group C and D at 1, 2, 4, and 6 weeks after operation, and the prol iferation cells in group A and B were less than that in group C and D at 1, 2, and 4 weeks after operation. The thickness of the intima, the degree of intima hyperplasia, the degree of vessel lumen stenosis of four groups at different time points were as follows: at 1 week after operation, group A [(12.69 ± 1.68) μm, 0.73 ± 0.05, 0.025 ± 0.003], group B [(17.52 ± 2.01) μm, 0.86 ± 0.06, 0.027 ± 0.004], group C [(21.92 ± 1.85) μm, 1.06 ± 0.09, 0.036 ± 0.006] and group D [(26.45 ± 3.86) μm, 1.18 ± 0.08, 0.041 ± 0.005]; at 2 weeks after operation, group A [(24.61 ± 2.91) μm, 0.86 ± 0.06, 0.047 ± 0.003], group B [(37.28 ± 2.78) μm, 1.17 ± 0.09, 0.060 ± 0.004], group C [(46.52 ± 2.25) μm, 1.44 ± 0.08, 0.073 ± 0.003], and group D [(52.07 ± 3.29) μm, 1.45 ± 0.05, 0.081 ± 0.006]; at 4 weeks after operation, group A [(61.09 ± 6.84) μm, 1.38 ± 0.08, 0.106 ± 0.007], group B [(63.61 ± 8.25) μm, 1.40 ± 0.07, 0.107 ± 0.010], group C [(80.04 ± 7.65) μm, 1.64 ± 0.07, 0.129 ± 0.011], and group D [(84.45 ± 9.39) μm, 1.68 ± 0.10, 0.139 ± 0.014]; at 6 weeks after operation, group A [(65.27 ± 5.25) μm, 1.46 ± 0.07, 0.113 ± 0.005], group B [(65.82 ± 7.12) μm, 1.45 ± 0.05, 0.112 ± 0.011], group C [(84.45 ± 9.39) μm, 1.69 ± 0.09, 0.135 ± 0.007], and group D [(87.27 ± 8.96) μm, 1.76 ± 0.05, 0.140 ± 0.012]. Group A and B were inferior to group C and D in terms of the above three parameters and cell prol iferation index 1, 2 and 4 weeks after operation (P lt; 0.05). Group A and B were superior to group C and D in terms of cell apoptosis index of intima and media 1 and 2 weeks after operation (P lt; 0.05). Transmission electron microscope observation showed that the synthetic cell organelles such as rough endoplasmic reticulum, golgi apparatus, and ribosome in group A and B were obviously less than those in group C and D (P lt; 0.05). Conclusion Topicalappl ication of 5-FU can effectively inhibit intima hyperplasia of the vein grafts.
This study was performed on canine femoral veins which were interpositionally implanted into the femoral arteries and the investigation was in terms of zero-stress state, compliance and hemodynamic assessment. The results revealed that the vein grafts had the similar characteristics of compliance with the normal veins. Using Doppler ultrasonography to monitor the blood flow velocity through the vein grafts, the hemodynamic parameters such as pulsatility index (PI) and blood flow volume were evaluated consecutively within one month after the operations .No significant differences were found between these parameters at different time points. It was suggested that autogenous vein graft had an adaptive course when operating in an arterial hemodynamic circumstances and It’s mechanical changes did not bear upon the hemodynamics through the vein graft.
Objective To investigate the effect and mechanism of epigallocatechin-3-gallate (EGCG) on restenosis of the vein graft. Methods Totally 90 Sprague-Dawley rats were randomly divided a the control group, a vein graft group and an EGCG+vein graft group. At week 1, 2 and 4, the intimal and tunica thickness of the venous graft wall was evaluated by hematoxylin-eosin staining, and the expression of Ki-67 was assessed by immunohistochemistry analysis, and then the expression of hairy and enhancer of split-1 (HES1) was measured by Western blot assay. Results At week 2, the intimal thickness (46.76±4.89 μmvs. 8.93±0.82 μm, 46.76±4.89 μmvs. 34.24±3.57 μm), tunica thickness (47.28±4.37vs. 16.33±1.52 μm, 47.28±4.37vs. 36.27±3.29 μm), positive cell rate of Ki-67 (21.59%±2.29%vs. 1.12%±0.22%, 21.59%±2.29%vs. 15.38%±1.30%), expression of HES1 respectively increased in the experimental group than those in the control group and the EGCG+vein graft group (P<0.05, respectively). At week 4, the intimal thickness (66.38±6.23 μmvs. 8.29±0.79 μm, 66.38±6.23 μmvs. 48.39±4.23 μm), tunica thickness (63.27±6.18 μmvs. 15.29±1.49 μm, 63.27±6.18 μmvs. 44.63±4.49 μm), positive cell rate of Ki-67 (33.19%±3.03%vs. 1.09%±0.19%, 33.19%±3.03%vs. 24.37%±2.73%), expression of HES1 increased in the experimental group than those in the control group and EGCG+vein graft group (P<0.05, respectively). Conclusion EGCG may inhibite restenosis of vein graft by inhibiting Notch signal pathway.