抄録
This paper describes an effect of using new ferrous polycrystalline shape-memory alloy showing huge superelasticity and higher stiffness as a self-expanding stent material. In this research, stent deployment analysis was conducted by using finite element analysis (FEM) software ANSYS 15.0. Nitinol self-expanding stents are widely used for artery stenosis treatments due to their high flexibility. However, the radial stiffness of self-expanding stents is low compared to balloon-expanding stents. Stent, artery, plaque, and sheath models were made for FEM analyses and the analytical results after deployment of nitinol and ferrous alloy stents were compared. In addition, two methods of the unsheathing were studied: (1) the conventional method where a stent comes out from one end of the sheath and (2) a new method in which stent comes out from the center of the sheath. FEM results showed that the radial force of the stent made of the new ferrous alloy was higher than those of nitinol. Meaning that the ferrous alloy stent displaces the plaque more than the nitinol stent. Furthermore, the plaque was displaced more using the new method of unsheathing, and the ends of the artery without the plaque showed smaller displacement. These results suggest the effectiveness of using the ferrous alloy for self-expanding stent.
