College of Mechanical Engineering, Inner Mongolia University of Technology, Hohhot, 010000, PR China.
College of Mechanical Engineering, Inner Mongolia University of Technology, Hohhot, 010000, PR China.
Comput Biol Med. 2024 Mar;170:107968. doi: 10.1016/j.compbiomed.2024.107968. Epub 2024 Jan 6.
When performing stent intervention for iliac vein compression syndrome, the operator selects the appropriate stent and determines its implantation depth according to the type and severity of iliac vein stenosis in the patient. However, there is still uncertainty regarding how the structure of the stent and its implantation depth affect hemodynamics at the site of lesion. In this paper, we analyzed three commonly used stents (Vena stent from Venmedtch, Venovo from Bard, and Smart stent from Cordis) with different implantation depths (0, 10, 20 mm) using computational fluid dynamics (CFD). We focused on evaluating hemorheological parameters such as time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), etc., within one pulsatile cycle after stent implantation. The correlation between geometric parameters of the stents and hemodynamic indicators was assessed using Pearson correlation coefficient (r), which was further validated through PIV velocity measurement experiment. The results revealed that an increase in implantation depth led to a more pronounced disturbance effect on blood flow at bifurcation for densely arranged support body-type stents. This effect was particularly significant during periods of smooth blood flow. On the other hand, crown-shaped Vena stents exhibited relatively less disruption to blood flow post-implantation. Implantation depth showed a strong negative correlation with TAWSS but a strong positive correlation with OSI and RRT. These findings suggest an increased risk of thrombosis at iliac vein bifurcation following stent placement. Amongst all three tested stents, Vena Stent demonstrated more favorable periodic parameters after implantation compared to others. These results provide valuable theoretical insights into understanding contralateral circulation thrombosis associated with iliac vein stenting.
在进行髂静脉压迫综合征的支架介入治疗时，术者根据患者髂静脉狭窄的类型和严重程度选择合适的支架，并确定其植入深度。然而，支架的结构及其植入深度如何影响病变部位的血液动力学仍然存在不确定性。在本文中，我们使用计算流体动力学（CFD）分析了三种常用的支架（Venmedtch 的 Vena 支架、Bard 的 Venovo 支架和 Cordis 的 Smart 支架），它们的植入深度分别为 0、10 和 20mm。我们重点评估了支架植入后一个脉动周期内的时均壁切应力（TAWSS）、振荡剪切指数（OSI）等血液流变学参数。使用皮尔逊相关系数（r）评估支架的几何参数与血流动力学指标之间的相关性，并通过 PIV 速度测量实验进行验证。结果表明，对于密集支撑体型支架，植入深度的增加会导致分叉处血流的干扰效应更加明显，尤其是在血流平稳期。另一方面，冠形 Vena 支架植入后对血流的干扰相对较小。植入深度与 TAWSS 呈强负相关，与 OSI 和 RRT 呈强正相关。这些发现表明支架放置后髂静脉分叉处发生血栓形成的风险增加。在所有三种测试的支架中，Vena 支架植入后的周期性参数表现更为理想。这些结果为理解髂静脉支架置入后相关的侧支循环血栓形成提供了有价值的理论见解。
