压握状态下不同结构支架的力学分析

Mechanical Analyses of Stents with Different Structures under Compressing State

摘要: 研究不同连接筋结构的血管支架的压握性能及支架在压握状态下的柔顺性性能，为支架的设计、开发及介入治疗提供科学的指导。利用Pro/E三维软件构建三种不同链接筋的支架模型。根据支架连接筋的结构分别称为L-支架、V-支架和S-支架。应用ABAQUS软件模拟3种不同链接筋支架的压握和弯曲过程，并进一步分析3种支架的压握性能和柔顺性。在支架压握过程中，L-支架、V-支架和S-支架的弹性回弹率分别为2.67%、6.00%和11.30%，轴向伸长率分别是1.74%、1.57%和2.61%。3种支架在压握状态下的弯曲过程中，L-支架上的应力峰值最小，3种支架端面中心点的位移分别为0.135 mm、0.578 mm和0.675 mm。结论为：L-支架压握后的回弹率最小，压握效果最好；V-支架的轴向伸长率最小，方便在血管中的运输；S-支架在压握状态下的柔顺性最好，较易送达迂曲的血管。

Abstract: In order to provide scientific guidance of design and development of stents and interventional treatment, the crimping properties and the flexibilities under crimping of the stents with different structures of connecting ribs were studied in this paper. The models of three different structures of connecting ribs were built by commercial software. L-stent, V-stent and S-stent were defined according to different link structures. Finite element analysis was carried out to analyze the crimping properties of three kinds of stents, and the flexibility under crimping was further researched. In the course of the crimping, the resilient rates of L-stent, V-stent and S-stent were respectively 2.67%, 6.00% and 11.30%, and axial elongations were respectively 1.74%, 1.57% and 2.61%. Under the crimping, the peak stress of L-stent had the minimum distribution compared to the others. Three stents displacements of the center of the end face were respectively 0.135 mm, 0.578 mm and 0.675 mm. In conclusion, L-stent had the best performance of crimping as it’s the minimum resilient rate after crimping; V-stent was suitable for transport in the vessels because it's the minimum axial elongation. S-stent had the best flexibility which was easier to reach tortuous vessels.