Establishment Of Animal Model Of May-Thurner Syndrome And Intracavitary Interventional Therapy

Part1The establishment of pig model of compression of veinObjective:To explore the method of establishing a stable and reliable model of iliac vein compression of small pigs for experiment.and to provide experimental basis for fur-ther study of the pathological mechanism of Thurner-May syndrome.Materials and methods:27 mini pigs were selected,The 15 of them were used to make the animal model of iliac vein compression of small experimental pigs.Conventional surgery area disinfection,shop sterile surgical towels single,A fler successful anesthesia,femoral vein was successful punctured,then inserted the loach guide wire,under the guidance of loach guide wire,inserted the catheter sheath.The diameter of the iliac vein,inferior vena cava,ascular wall ’s shape and blood flow velocity of the iliac vein and inferior vena cava were observed by the catheter insertion of 5F pig tail catheter to the right iliac vein.The small experimeltal pigs were randomly divided into external iliac vein group,comm-on iliac vein group and common iliac+iliac vein group.there were 5 cases in each group.Then a length of about 15cm incision was made in the abdomen of a small expcreimental pig.And next moment we cut the skin,subcutaneous tissue,anterior rectus sheath,blunt dissection of the rectus incision,posterior rectus sheath,perito-neum,opened the abdominal layer,pushed the intestines,exposed the inferior vena cava,the left common iliac vein,the left external iliac vein and the left internal iliac vein.The left external iliac vein was ligated at far heart end about 2cm of the left side of the external iliac vein into the left common iliac vein in the external iliac vein group,the left common iliac vein was ligated at proximal end 1cm of the confluence of the left external iliac vein and internal iliac vein in the common iliac vein group,combination with ligation of the left common iliac vein and the left common iiiac vein in the common iliac+iliac vein group.After the operation,the abdolinal cavity was closed by layer by layer suture,After waking up,the small experimental pigs were sent back to the experimental center,then Angiography review to observe the imaging findings of venous thrombosis and the establishment of collateral circulation after Iliac vein compression two weeks,one month and two months after surgery.The pigs were executed two months later,and the inferior vena cava and iliac vein were taken out for pathological examination.The other 12 of them were used to explore the way of thrombosis of inferior vena cava by slowing down the blood flow using the balloon and injecting thrombin,placing the venous filter,and pulling the vein filter to damage the vein wall and so on.Result:All surgical operations were successfully conpleted,The vein blood block can be seen by immediate angiography after ligation of the vein blood vessel,Thrombosis can be observed in the iliac vessels of the external iliac vein group and common iliac+iliac vein group tvvo weeks after the operation,while there were no thrombosis in the iliac vessels of common iliac vein group.Pathological examination revealed that the intimal thickening of the local blood vessel wall was obviously increased.Thrombosis can be formed in the inferior vena cava by balloon occlusion or slow down the inferior vena cava and thrombin injection,Inferior vena cava filter and damage inferior vena cava vein wall.Conclusion:Through the ligation of the left external iliac vein and ligation of the left common iliac and iliac vein can simulation of left common iliac vein compression,The ligation of left external iliac vein and combined with ligation of left common iliac and iliac vein of small experimental pigs can be stable and reliable iliac vein compression mo-del,It can provide experimental basis for further study of the pathological mechanism of May-Thurner syndrome.Thrombosis in inferior vena cava by slowing down the blood flow using theballoon and injecting thrombin.placing the venous filter,and pulling the vein filter to damage the vein walli which indicates that blood flow blockage,blood coagulation and vascular wall injury play an important role in the formation of thrombosis.Part twoInterventional treatment of left lower extremity deep venous thrombosis with May-Thurner syndromeObjective:To study the clinical value of the interventional endovascular techniques(cath-eter-directed thrombolysis,balloon dilatation angioplasty and/or stent implantation)treatment for left lower extremity deep vein thrombosis secondary to may-Thurner syndrome,in order to develop a interventional therapy clinical path for left lower ex-tremity deep vein thrombosis secondary to may-Thurner syndrome.Materials and methods:60 patients with the left iliac vein compression and acute left lower extremity deep vein thrombosis were collected,16 cases of patients suffered from iliac femoral venous thrombosis,24 cases of patients suffered from femoral popliteal vein throm?bosis,iliac femoral popliteal vein thrombosis were in 14 cases,and iliac femoral pop-liteal vein and deep venous thrombosis of the calf were in 6 cases.All the patients were divied into two groups according to whether the stents were implanted,Balloon group patients were only performed of transluminal balloon dilatation(PTA),stent group patients were performed of PTA and implantation of iliac vein stent.All the patients were examined by color Doppler ultrasound,CT scan and lower limb deep vein contrast examCatheter thrombolysisliy before thrombolytic therapy,UniFuse multi-side hole thrombolysis catheter was inserted for catheter thrombolysis from the right femoral vein "crosses" in the patients with iliofemoral venous thrombosis,The dose of urokinase was 500 thousand u/days,and 1～3 days were reviewed,Continuous thrombolysis according to thrombus dissolution,and the position of the catheter was adjusted according to the results of the angiography,low-molecular-weight Heparin Sodium Injection(5000U,ql2h)was employed at the same time,Coagulation function was must be dynamically monitored during thronbolysis.and thrombolysis must be stopped once the fibrous protein was less than 1g/L.The atients with Popliteal vein thrombosis or Iliac femoral popliteal vein and calf vein thrombosis need combinedwith thrombolysis through dorsal vein.After complete dissolution of the thrombus.Balloon group patients were only performed of transluminal balloon dilatation(PTA).stent group patients were performed of PTA and implantation of iliac vein stent.All the ilter was taken out at last.the thrombosis clearance rate were observed.the iliae vein pateney ot the 3 months,6 months and 1 year,the thrombus recurrence rate,the complications and the rate of Post thrombotic syndrome were analyzed,and the iliac vein patency short-term rates between the balloon dilatation and balloon dilatationcombined with stent implanta-tion were compared.Result:All of the techniques were completed successfully include vascular ultrasound.CT enhancement scanning,arteriography of lower extremity deep vein,catheter-dir-ected thrombolysis balloon dilatation angioplasty and/or stent implantation.The te-chnical success rate was 100%.The numbers of lower limb swelling in balloon group postoperative 3M,6M.1Y were significantly higher than that in stent group,and the diftcrcncc was significant statistically(P<0.05).The patency of 6M and 1Y in balloon group was siginillcant-ly lower than that in stent group,and the difference was statistically signilleant(P<0.05).There were 2 cases of recurrence of lower extremity deep venous thrombo-sis after 7 months of operation,and no patients with deep venous thrombosis of lowerlimb in stent group.Conclusion:For iliac vein compression syndrome complicated by deep vein thrombosis,the combination of inferior vena cava filter implantation,catheterdirected thrombolysis via jugular vein,and balloon dilatation together with stent placement for compressed iliac vein is a safe,mini-invasive and effective therapy.It is well worth popularizing this technique in clinical practice.Iliac vein balloon dilation combined with stent implantation can significantly increase the short-term patency rate of iliac vein than iliac vein balloon dilatation simply in the treatment of stenosis of occlusion of iliac vein compression.