Ultrasonic Evaluation Of The Stability Of Deep Vein Thrombosis In Different Parts Of The Lower Extremities And Postoperative Effect In Patients With Inferior Vena Cava Filter Implantation

Chapter Ⅰ Correlation between deep venous thrombosis in different parts of lower extremity and pulmonary embolismObjective:The correlation between deep vein thrombosis(DVT)and pulmonary embolism(PE)in different parts of the lower extremity was analyzed by deep vein color Doppler flow imaging(CDFI)examination and pulmonary CT angiography(CTA).The stability of DVT is assessed,and the risk factors leading to PE are found to provide the basis for clinical diagnosis and early intervention of patients with DVT.Methods:The clinical data of 300 patients with DVT admitted from January 2017 to December 2020 were retrospectively analyzed.All patients underwent CDFI and pulmonary artery CTA.Except for 4 patients with only inferior vena cava thrombosis,the remaining 296 patients were included in the study.Among the 296 patients,178 were male,aged 30-80 years,and 118 were female,aged 33-78.According to the different location of thrombus,it is divided into central,peripheral and mixed DVT.According to the side of the affected limb,it is divided into unilateral and bilateral,and unilateral is divided into left and right.To analyze whether there is a correlation between patient gender,DVT type,affected limb and the incidence of PE.Results:Among the 296 patients,178 were male and 118 female;The patients with central,peripheral and mixed type was in 42,149 and 105 patients respectively;There are 242 cases of unilateral limb(including 149 cases of left limb and 93 cases of right limb),54 cases of bilateral limbs.All patients underwent pulmonary artery CTA examination and a total of 71 patients were confirmed PE,with the total incidence of 24.0%.1.Among the 178 male patients,45 were PE patients,and the incidence rate was 25.3%;among the 118 female patients,26 were PE patients,and the incidence rate was 22.0%.After chi-square test,P>0.05(X2=0.410,P=0.522),the difference was not statistically significant,suggesting that the incidence of PE was not related to the gender of the patients;2.Among the 42 central DVT patients,14 were PE patients.;among the 149 peripheral DVT patients,25 were PE patients,and the incidence rate was 16.8%;among the 105 complex DVT patients,32 were PE patients,and the incidence rate was 30.5%.After chi-square test,P<0.05(X2=8.684,P=0.013),the difference was statistically significant,indicating that the incidence of PE in patients with central and mixed DVT was higher than that in patients with peripheral DVT;3.Among the 149 cases of peripheral DVT,8 patients with pure femoral vein thrombosis,including 2 patients with PE,the incidence rate was 25.0%;19 patients with thrombosis in the main deep veins of the calf(popliteal vein,peroneal vein,posterior tibial vein and anterior tibial vein),including 5 patients with PE,the incidence rate was 26.3%;there were 75 patients with simple calf intermuscular venous thrombosis,including 6 patients with PE,with an incidence rate of 8.0%;47 patients with femoral vein complicated with calf trunk deep vein thrombosis,including 12 patients with PE,with an incidence rate of 8.0%.25.5%;by chi-square test,P<0.05(X2=8.343,P=0.039),the difference was statistically significant,indicating that there is a significant correlation between the thrombus site and PE in patients with peripheral DVT,that is,the occurrence of simple calf intermuscular vein thrombosis The odds of PE were significantly lower than those of patients with peripheral DVT at other sites.4.Among the 242 patients with unilateral lower extremity DVT,there were 52 patients with PE,with an incidence rate of 21.5%;among the 54 patients with bilateral lower extremity DVT,there were 19 patients with PE,with an incidence rate of 35.2%.After chi-square test,P>0.05(X2=4.543,P=0.033),the difference was statistically significant,suggesting that the incidence of PE in patients with bilateral lower extremity DVT is higher than that of unilateral.Among the 149 patients with DVT of the left lower extremity,31 patients were with PE,and the incidence rate was 20.8%.Among the 93 patients with DVT of the right lower extremity,there were 21 patients with PE,and the incidence rate was 22.6%.After chi-square test,P>0.05(X2=0.107,P=0.744),the difference was not statistically significant,suggesting that there was no significant difference in the incidence of PE in patients with left and right lower extremity DVT.Conclusion:In lower extremity DVT cases,the incidence of PE has nothing to do with the gender of the patient;it is significantly correlated with the type of lower extremity DVT,that is,the incidence of PE in patients with central and mixed DVT is higher than that in patients with peripheral DVT;the location of thrombus in patients with peripheral DVT is related to There is also a significant correlation between the incidences of PE,and the incidence of PE in simple intermuscular venous thrombosis of the calf is significantly lower than that in patients with DVT in other parts;there is also a correlation with the side of the affected limb,and the incidence of PE in patients with bilateral lower extremity DVT is higher than that in unilateral DVT patients The rate is high,which can provide imaging basis for early clinical intervention.Chapter Ⅱ Evaluation of inferior vena cava filter implantation using color Doppler ultrasoundObjective:To compare the incidence of pulmonary embolism in patients with lower extremity DVT in different parts of the two groups with and without IVCF implantation and color Doppler ultrasound on postoperative IVCF.Follow-up was performed to evaluate the preventive effect of IVCF implantation on PE due to thrombus shedding in DVT patients,and to provide imaging evidence for the selection of clinical treatment methods.Methods:1.A retrospective analysis of 200 patients with lower extremity DVT who underwent IVCF implantation and those who did not undergo IVCF implantation from January 2017 to June 2021 were retrospectively analyzed.All patients underwent color Doppler ultrasonography of inferior vena cava and deep veins of both lower extremities and pulmonary artery CTA.The 400 patients were divided into filter placement group and non-filter placement group.According to the different location of thrombus,it is divided into central,peripheral and mixed DVT.The chi-square test was used to compare and analyze whether there was a significant difference in the incidence of pulmonary embolism between the two groups of patients with different types of lower extremity DVT,so as to evaluate the preventive effect of IVCF implantation on PE caused by thrombus shedding in patients with DVT;2.Peripheral DVT is divided into four categories:femoral vein thrombosis,calf trunk deep vein thrombosis,simple calf intermuscular vein thrombosis,and femoral vein combined with calf trunk deep vein thrombosis.Fisher’s exact test was used to compare and analyze whether there was a significant difference in the incidence of PE between the two groups of patients with peripheral DVT in different parts,so as to suggest which parts of the patients with peripheral DVT can avoid complicated IVCF implantation and provide a reference for clinical practice.3.The 200 patients in the filter placement group who have been diagnosed with lower extremity DVT were evaluated by color Doppler ultrasound before filter placement,and the inferior vena cava,iliac vein and lower extremity vein were scanned,and the veins were observed for malformation,anatomical variation and blood flow.Unobstructed flow,determine the location and scope of thrombosis,and then perform angiography and inferior vena cava filter placement.Postoperative ultrasound observes the location,shape,and smooth blood flow of the filter,whether the filter has thrombosis,and whether the lower extremity DVT progresses.and other complications to follow up the diagnosis and treatment effect of IVCF implantation.Results:1.Among the 200 lower extremity DVT patients in the non-filter placement group,there were 42 patients with PE,and the incidence rate was 21.0%.Among the 200 lower extremity DVT patients in the filter placement group,there were 9 patients with PE,and the incidence rate was 4.5%,after the chi-square test,P<0.05(X2=24.473,P<0.001),the difference is statistically significant,indicating that there is a significant correlation between the filter placement and the incidence of PE,that is,the incidence of PE in the filter placement group It was significantly lower than the non-implantation group(Table 3).2.For the peripheral DVT of two different parts,which are pure femoral vein thrombosis and femoral vein combined with calf deep vein thrombosis,there are significant differences in the incidence of PE between the filter placement group and the non-filter placement group,both P values<0.05(P values were 0.033 and 0.017,respectively);however,there was no difference in the incidence of PE between the filter-placed and non-filter-placed groups for peripheral DVT in two different sites:deep venous thrombosis of the main calf and simple intermuscular venous thrombosis of the calf.Statistically significant,P values were all>0.05(P values were 0.184 and 0.492,respectively)(Table 4).3.Among the 200 patients with IVCF implantation,45 patients(45/200,22.5%)were diagnosed with thrombosis in the filter by ultrasound,21 patients(21/200,10.5%)were diagnosed with thrombosis in the inferior vena cava,and DVT progressed in the lower extremity.27 cases(27/200,13.5%),including 4 cases of iliac-femoral vein thrombosis extending to the inferior vena cava,13 cases of simple calf intermuscular venous thrombosis involving the popliteal vein and femoral vein,and calf DVT spreading upward and involving the femur The veins and iliac veins were found in 7 cases,and the contralateral side had DVT in 3 cases.Inferior vena cava angiography as the standard,the accuracy of ultrasound diagnosis of intra-filter thrombosis was 87%(45/52),and the accuracy of inferior vena cava thrombosis was 100%(21/21).Conclusion:(1)There is a significant correlation between the placement of inferior vena cava filters and the incidence of PE.IVCF placement can significantly reduce the incidence of PE due to thrombus shedding in patients with lower extremity DVT.(2)When the patient only has calf deep vein thrombosis(such as popliteal,posterior tibial,peroneal,anterior tibial vein thrombosis,and calf intermuscular vein thrombosis),the incidence of PE is not related to whether the filter is placed or not,suggesting that it can be avoided clinically.Complicated IVCF placement in order to reduce the complications caused by the operation and reduce the economic burden of the patient.(3)Color Doppler ultrasound can accurately judge the lesion range of lower extremity DVT after IVCF implantation,the position,shape,blood flow and postoperative complications of the filter,and the preventive effect of clinical IVCF implantation.Evaluation plays an important role.