支架植入是用于治疗冠状动脉疾病的标准医疗程序。多年来,已经探索了各种不同的支架设计,这些支架有一系列的局限性,包括晚期支架内再狭窄(由于径向强度低),缩短,径向反冲,等。相反,采用拉胀设计的支架,以负泊松比为特征,显示独特的变形特性,导致增强的机械性能,在其径向强度方面,径向反冲,缩短,还有更多.在这项研究中,我们分析了一种新型的双箭头(DA)拉胀支架,旨在克服与传统支架相关的局限性,特别是在径向强度方面,缩短,和径向反冲。首先对DA的单元环结构进行了参数分析,通过评估三个设计参数(角度,振幅,和宽度)使用有限元分析对机械特性(径向强度和径向反冲)。发现支柱的宽度是支架结构性能的主要决定因素。因此,发现角度和宽度对改变支架的机械性能影响最小。执行参数分析后,选择最佳设计因素来设计全长DA拉胀支架。在与Cypher™商业支架的案例研究中,评估并比较了DA拉胀支架的机械特性。DA拉胀支架的径向强度为7.26N/mm,这是Cypher™商业支架径向强度的两倍以上。此外,所提出的支架具有降低的径向反冲性能,并完全消除了支架缩短问题,这表明了拟议的拉胀支架的优越的机械性能及其作为未来支架设计的有希望的候选人的潜力。
A stent implantation is a standard medical procedure for treating coronary artery diseases. Over the years, various different designs have been explored for the stents which come with a range of limitations, including late in-stent restenosis (due to low radial strength), foreshortening, radial recoil, etc. Contrary, stents with auxetic design, characterized by a negative Poisson\'s ratio, display unique deformation characteristics that result in enhanced mechanical properties in terms of its radial strength, radial recoil, foreshortening, and more. In this study, we have analysed a novel double arrowhead (DA) auxetic stent that aims to overcome the limitations associated with traditional stents, specifically in terms of radial strength, foreshortening, and radial recoil. The parametric analysis was done initially on the DA\'s unit ring structure to optimize the design by evaluating the effect of three design parameters (angle, amplitude, and width) on the mechanical characteristics (radial strength and radial recoil) using finite element analysis. The width of the strut was found to be the primary determinant of the stent structure\'s properties. Consequently, the angle and width were found to have the least effect on altering the stent\'s mechanical properties. After performing the parametric analysis, optimal design factors were selected to design the full-length DA auxetic stent. The mechanical characteristics of the DA auxetic stent were assessed and compared in a case study with the Cypher™ commercial stent. The radial strength of DA auxetic stent was found to be 7.26 N/mm, which is more than double the Cypher™ commercial stent\'s radial strength. Additionally, the proposed stent possesses reduced radial recoil property and completely eliminates the stent foreshortening issue, which shows the superior mechanical properties of the proposed auxetic stent and its potential as a promising candidate for future stent designs.