The current finite element analysis of vascular stent expansion does not take into account the effect of the stent release pose on the expansion results. In this study, stent and vessel model were established by Pro/E. Five kinds of finite element assembly models were constructed by ABAQUS, including 0 degree without eccentricity model, 3 degree without eccentricity model, 5 degree without eccentricity model, 0 degree axial eccentricity model and 0 degree radial eccentricity model. These models were divided into two groups of experiments for numerical simulation with respect to angle and eccentricity. The mechanical parameters such as foreshortening rate, radial recoil rate and dog boning rate were calculated. The influence of angle and eccentricity on the numerical simulation was obtained by comparative analysis. Calculation results showed that the residual stenosis rates were 38.3%, 38.4%, 38.4%, 35.7% and 38.2% respectively for the 5 models. The results indicate that the pose has less effect on the numerical simulation results so that it can be neglected when the accuracy of the result is not highly required, and the basic model as 0 degree without eccentricity model is feasible for numerical simulation.
目前关于血管支架扩张的有限元分析并未将支架释放位姿这一因素对扩张结果的影响考虑在内。本研究利用 Pro/E 软件建立了支架和血管模型，通过 ABAQUS 软件构建了 5 种有限元装配模型，分别为 0 度无偏心模型、3 度无偏心模型、5 度无偏心模型、0 度轴向偏心模型和 0 度径向偏心模型，分为角度和偏心两组实验进行扩张模拟。计算了各模型的轴向缩短率、径向回弹率、狗骨头率等力学参数，通过比较分析，得出支架虚拟释放时的角度、偏心对数值模拟的影响。计算得到 5 种模型支架扩张后的残余狭窄率分别为 38.3%、38.4%、38.4%、35.7%、38.2%。研究表明位姿对数值模拟结果的影响较小，在对结果精度要求不高的情况下可以忽略这种影响，采用 0 角度无偏心的基本模型进行扩张模拟。.
Keywords: endovascular stent; finite element analysis; mechanical properties; numerical simulation.