Institute of Civil Engineering and Architecture, Southwest University of Science and Technology, Mianyang 621010, China.
Department of Cardiology, Mianyang Central Hospital, Mianyang 621000, China.
Comput Methods Programs Biomed. 2024 Jan;243:107926. doi: 10.1016/j.cmpb.2023.107926. Epub 2023 Nov 13.
Carotid webs (CWs), lesions in the carotid arteries, are gaining research interest due to the unclear link to ischemic stroke. Similarity to atherosclerosis in lesion location adds the complexity. The main purpose of study is to investigate the hemodynamic effects of CWs at different locations in carotid arteries.
Three types of models with CWs were reconstructed from the CTA dataset of 8 healthy carotid arteries (Models A: CWs at the common carotid artery; B: at the origin of internal carotid artery; C: at the carotid sinus). Wall shear stress (WSS)-based parameters, including time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), relative residence time (RRT), and endothelial cell activation potential (ECAP) were analyzed. A thrombus growth model was also incorporated to assess long-term thrombus formation across different carotid webs locations.
Models A exhibited helical flow, whereas models B and C showed disturbed flow in the carotid sinus. Recirculation in Models A and B was mainly downstream of CWs, while Models C had both upstream and downstream recirculation. In addition, models A had higher overall TAWSS levels, with the smallest region of TAWSS < 0.4 pa (7.78 ± 8.35%). In contrast, Models C had larger areas with TAWSS < 0.4 pa, RRT > 100, and ECAP > 1.5, accounting for 14.18 ± 5.28%, 1.51 ± 1.17%, and 10.36 ± 4.10%, respectively. Noting that thrombus volume was highest in Models C (7.20 ± 3.95%).
Numerical simulations indicate that: 1) CWs have less hemodynamic impact when located in the CCA, but may increase flow resistance leading to distal branch ischemia; 2) CWs contribute to thrombus formation, primarily downstream in the common carotid artery and internal carotid artery origin, and both upstream and downstream in the sinus; 3) CWs at the origin of the ICA are more likely to result in disturbed blood flow patterns and thrombus aggregation than the other two locations, which may increase the risk of ischemic stroke in distal cerebral arteries.
颈动脉壁（CW）是颈动脉中的病变，由于与缺血性中风的关联不明确而引起研究关注。病变位置与动脉粥样硬化的相似性增加了其复杂性。本研究的主要目的是研究颈动脉内不同位置 CW 的血液动力学影响。
从 8 例健康颈动脉 CTA 数据集重建了 3 种 CW 模型（模型 A：颈总动脉处 CW；B：颈内动脉起始处 CW；C：颈动脉窦处 CW）。分析了基于壁面剪切应力（WSS）的参数，包括时均壁面剪切应力（TAWSS）、振荡剪切指数（OSI）、相对居留时间（RRT）和内皮细胞激活潜能（ECAP）。还纳入了血栓生长模型，以评估不同颈动脉壁位置的长期血栓形成。
模型 A 显示出螺旋流，而模型 B 和 C 在颈动脉窦处显示出紊乱的血流。模型 A 和 B 的再循环主要位于 CW 下游，而模型 C 则有上游和下游的再循环。此外，模型 A 的整体 TAWSS 水平较高，最小 TAWSS<0.4pa 区域为 7.78±8.35%。相比之下，模型 C 的 TAWSS<0.4pa、RRT>100 和 ECAP>1.5 的区域较大，分别占 14.18±5.28%、1.51±1.17%和 10.36±4.10%。值得注意的是，模型 C 中的血栓体积最大（7.20±3.95%）。
数值模拟表明：1）CW 位于 CCA 时对血流动力学的影响较小，但可能会增加血流阻力，导致远端分支缺血；2）CW 导致血栓形成，主要在颈总动脉和颈内动脉起始处的下游，以及窦内的上游和下游；3）ICA 起源处的 CW 比其他两个位置更容易导致血流模式紊乱和血栓聚集，这可能会增加远端大脑动脉缺血性中风的风险。
