基于计算流体力学的Stanford B型主动脉夹层血流动力学分析

目的通过计算流体力学(computational fluid dynamics, CFD)分析Stanford B型夹层的血流动力学参数,从而有效全面评估疾病。方法基于1例复杂的Stanford B型主动脉夹层患者的增强CTA影像,构建三维模型和血流动力学的数值模拟研究,分析流场速度分布、夹层破口剖面速度分布以及壁面切应力。结果该病例在夹层入口、出口处的血液流速分别最高达到1.2、2 m/s,为进一步预测夹层破裂位置和评估夹层破裂风险提供依据。在夹层破口附近的假腔壁面形成明显的低壁面切应力区,与患者体内血栓位置相一致。结论 CFD能有效分析复杂主动脉夹层的血流动力学特征,获得主动脉弓部及其降主动脉的剪切力与主动脉夹层发生的相关性,有助于指导临床对主动脉进行功能学评估,进而预防疾病发生。

Hemodynamic Analysis of Stanford Type B Aortic Dissection Based on Computational Fluid Dynamics

Objective To analyze the hemodynamic parameters of Stanford type B aortic dissection based on computational fluid dynamics (CFD), so as to make a thorough evaluation of the disease. Methods Based on CTA images of a patient with complex Stanford type B aortic dissection, the three-dimensional model and hemodynamic numerical simulation were carried out to analyze the velocity distribution of flow field and intersecting fracture profile, as well as the wall shear stress. Results The maximum velocity of blood flow at the entry tear and re-entry tear could reach 1.2 m/s and 2 m/s, respectively, providing references for further evaluation on aortic rupture position and prediction of aortic rupture risk. An obvious low wall shear stress zone was formed on false lumen wall near the entry tear, which was consistent with the thrombus position in the patient. Conclusions CFD could effectively analyze the hemodynamic characteristics of complex aortic dissection, obtain the correlation between aortic dissection and wall shear stress at aorta arch and descending aorta, which contributed to guiding clinical assessment of aortic function for preventing the diseases.