Study Of Computational Fluid Dynamics In Hemodynamics Of Patients With Iliac Vein Stenosis

Objective In this studyr,the hemodynamic parameters of patients with real iliac vein compression syndrome(IVCS)were analyzed by computational fluid dynamics(CFD)technology.The hemodynamic characteristics of patients with IVCS were explored,and the relationship between different stenosis degrees and hemodynamic parameters was analyzed.Methods 30 patients with IVCS who were admitted to the General Hospital of ningxia Medical University from January 2019 to June 2022 were collected.The CTV image data of the patients were obtained.The hemodynamic parameters of the patients with IVCS were obtained by CFD.The hemodynamic characteristics of patients with different degrees of stenosis were analyzed.The correlation between the degree of stenosis and hemodynamics in patients with IVCS was explored.The difference of fluid mechanics data between the affected side and the healthy side of patients with IVCS was explored.The correlation between hemodynamic parameters and clinical data such as villalta score was explored.Results After using CFD technology to analyze,it was found that the blood flow velocity at the stenosis of 50-69 % stenosis was 0.254 ± 0.037 m / s,the blood flow velocity at the stenosis of 70-89 % stenosis was 0.452 ± 0.078 m / s,and the blood flow velocity at the stenosis of ≥ 90 % stenosis was 0.809 ± 0.083 m / s.The difference in blood flow velocity between different stenosis degrees was statistically significant(P < 0.05).The wall pressure at the distal end of the stenosis of 50-69 % stenosis was 204.571 ± 62.122 Pa,and the pressure difference between the distal and proximal ends of the stenosis was 64.357 ± 18.744 Pa.The wall pressure at the distal end of the stenosis of 70-89 % stenosis was 447.556 ± 65.723 Pa,and the pressure difference was 186.222 ± 23.993 Pa.The wall pressure at the distal end of the stenosis of ≥90 % stenosis was 781.286 ± 87.204 Pa,and the pressure difference was 294.714± 49.809 Pa.The difference of pressure and pressure difference between different degrees of stenosis was statistically significant(P < 0.05).The wall shear stress(WSS)of 50-69 %stenosis was 2.981 ± 0.917 Pa,70-89 % stenosis was 9.067 ± 2.916 Pa,≥ 90 % stenosis was21.890 ± 3.305 Pa,the difference was statistically significant(P < 0.05).The wall pressure,blood flow velocity and WSS of the affected side and the healthy side were different,and these differences were statistically significant(P < 0.05).Spearman correlation analysis showed that hemodynamic parameters were correlated with the degree of stenosis(blood flow velocity : r = 0.963,P < 0.01,wall pressure : r = 0.882,P < 0.01,pressure difference : r =0.874,P < 0.01,wall shear stress : r = 0.906,P < 0.01).Pearson correlation analysis showed that hemodynamic parameters and stenosis rate were correlated with Villalta score(blood flow velocity : r = 0.911,P < 0.01,wall pressure : r = 0.794,P < 0.01,wall shear stress : r =0.863,P < 0.01,stenosis rate : r = 0.846,P < 0.01).Conclusions1.The hemodynamic parameters of IVCS patients with different degrees of stenosis are different,When the degree of stenosis increases,the hemodynamic parameters also increase.2.There are differences in hemodynamic parameters between the affected side and the healthy side of IVCS patients.3.The hemodynamic parameters and stenosis rate were positively correlated with the Villalta score,The hemodynamic parameters were more in line with the clinical symptoms and signs of the patients than the stenosis rate.