Topology optimization of coronary artery stent considering structural and hemodynamic parameters

Abstract

In the present study, the impact of geometric variables and structural features of stents on hemodynamic parameters is investigated. Intravascular stent implantation is a treatment method whose success largely depends on the geometric structure of the stent and its effect on hemodynamic parameters. Medical devices called stents are inserted into arteries to restore blood flow when an artery is blocked. In this research, an optimal stent was designed and its effect compared to the common commercial stent used for coronary arteries was investigated and compared. It has been found that the geometry of the stent has an effective impact on the wall shear stress in the stented artery. Therefore, in this article, the importance of stent structures in the treatment of the coronary artery disease is discussed. For this purpose, first, an optimal stent is created with the topology optimization technique to find the best structure in the stent design. Finally, the optimized stent is numerically verified with ANSYS software and compared with existing commercial stents, and then the prototype is fabricated using additive manufacturing techniques. Commercial software ABAQUS, SolidWorks, and ANSYS are used in this research. The results showed that in optimizing a square plate, a sample with a minimum residual volume limit equal to 10 and 7 % can be selected as the optimal state. The results indicate that the new design can improve the distribution of wall shear stresses to reduce the adverse hemodynamic changes. Therefore, the proposed stent geometric structure can help improve the treatment. Finally, the optimized stent along with a commercial stent was made with the 3D printing method.