The impact of stenosis treatment on the hemodynamic crosstalk between carotid arteries

Abstract Biomechanical analysis of crosstalk between the carotids remains poorly underexplored. This study aims to clarify the impact of severe carotid stenosis on the local hemodynamics of the opposite carotid artery, before and after treatment. Data from patients diagnosed with severe internal carotid artery stenosis (≥ 70%), treated with carotid artery stenting (CAS) or carotid endarterectomy (CEA) were analyzed. Both sides' anatomical and hemodynamic remodeling parameters were evaluated before and after treatment. Forty-two patients underwent computed tomography angiography (CTA) and phase-contrast magnetic resonance imaging (PC-MRI) to measure carotid diameters and flow rates in the common, internal, and external carotids (CCA, ICA, and ECA, respectively) before and after CAS or CEA. Additionally, patient-specific computational fluid dynamics (CFD) simulations were performed to calculate time-averaged wall shear stress (taWSS) before and after the treatment. Post-treatment analysis revealed anatomical and hemodynamic changes in the contralateral side. Specifically, there was a decrease in blood flow and an increase in vessel diameters, particularly in the CCA, of patients who had undergone CEA (pre vs. post: flow p = .029, diameter p = .007). Additionally, there was an increase in low taWSS areas in the SOI after the operation: CEA from 15.50 (10.80) % to 18.00 (20.25) %, CAS from 17.00 (15.55) % to 19.50 (20.50) %. The study revealed new anatomical and hemodynamic parameters changes in both carotids, offering insights into the interaction between stenotic and contralateral carotid arteries in post-operative conditions.摘要 迄今，颈动脉间交互作用的生物力学分析仍未得到充分探索。本研究旨在阐明重度颈动脉狭窄患者接受治疗前后，其对侧颈动脉的局部血流动力学变化。本研究对确诊为重度颈内动脉狭窄（狭窄程度≥70%）、且接受颈动脉支架置入术（carotid artery stenting, CAS）或颈动脉内膜切除术（carotid endarterectomy, CEA）的患者数据进行了分析。研究对患者双侧颈动脉的解剖学与血流动力学重塑参数在治疗前后均进行了评估。42名患者在接受CAS或CEA治疗前后，均接受了计算机断层血管造影（computed tomography angiography, CTA）与相位对比磁共振成像（phase-contrast magnetic resonance imaging, PC-MRI）检查，以测量颈总动脉（common carotid artery, CCA）、颈内动脉（internal carotid artery, ICA）及颈外动脉（external carotid artery, ECA）的管径与血流量。此外，本研究还开展了患者特异性计算流体动力学（computational fluid dynamics, CFD）模拟，以计算治疗前后的时间平均壁面切应力（time-averaged wall shear stress, taWSS）。术后分析结果显示，对侧颈动脉出现了解剖学与血流动力学层面的改变。具体而言，接受CEA治疗的患者，其颈总动脉的血流量出现下降、管径出现升高（术前vs术后：血流量p=0.029，管径p=0.007），该变化在颈总动脉中尤为显著。此外，术后感兴趣区域（study of interest, SOI）内的低taWSS区域占比出现升高：CEA组从15.50(10.80)%升至18.00(20.25)%，CAS组从17.00(15.55)%升至19.50(20.50)%。本研究揭示了双侧颈动脉的全新解剖学与血流动力学参数变化，为理解术后狭窄颈动脉与对侧颈动脉间的交互作用提供了新的视角。