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针对支架植入术后的冠脉血管内支架再狭窄问题,通过非线性有限元法建立弯曲冠脉-支架介入系统生物力学模型及冠脉支架纵向柔顺性计算模型,开展了冠脉支架结构设计对血管壁面损伤与再狭窄的影响机理研究。数值分析结果表明,弯曲血管在支架端部存在高应力梯度,所产生的最大应力是直冠脉的4~6倍,易于损伤血管从而形成血管内支架再狭窄问题。冠脉支架结构的纵向柔顺性对弯曲血管的整体应力水平具有显著的影响,C 型支架的纵向柔顺性远低于S型支架和N型支架,植入后所引起的血管整体应力水平最高；S型支架具有最好的纵向柔顺性,植入后所引起的血管整体应力水平最低。从支架与血管的相互作用以及支架纵向柔顺性的角度解释了临床中弯曲血管内支架再狭窄率较高的力学原因,为支架的临床选择及优化设计提供了重要指导作用。

The biomechanical model of curved vascular-coronary stent intervention system was established to in-vestigate the induced coronary restenosis by the stent implantation.The influence of stent design on vascular wall inj ure as well as subsequent restenosis was studied by analyzing the mechanical stimulus to the vascular wall.The numerical result indicated that there were extremely high stress gradient on the curved vascular adj a-cent to the stent terminal,where the maximum stress was as large as quadruple to sixfold counterpart on the straight vascular with more opportunity to vascular inj ure resulting in vascular restenosis.The longitudinal flex-ibility of the coronary stent was also found to remarkably influence the global stress level in the curved vascular. The longitudinal flexibility of the C-stent was far less than that of the S-stent and the N-stent,which induces the highest global stress level in the curved vascular by the C-stent intervention.The N-stent was provided with the more superior longitudinal flexibility to the C-stent and the S-stent,resulting in the lowest global stress lev-el in the curved vascular.Consequently the high restenosis rate in the curved vascular is revealed as the clinical manifestation by the stent interaction with coronary artery as well as the longitudinal flexibility of the stent.It provides the great guideline to the clinical option and the optimizational design of coronary stents.