Finite element analysis of NiTi self-expandable heart valve stent. (October 2019)

• Record Type: Journal Article
• Authors: Salemizadeh Parizi, Fatemeh; Mehrabi, Reza; Karamooz-Ravari, Mohammad Reza
• Is Part Of: Proceedings of the Institution of Mechanical Engineers. Volume 233:Number 10(2019)
• Page Start: 1042
• Page End: 1050
• Publication Date: 2019-10
• Subjects: Artificial heart valve -- radial force -- shape memory alloy -- self-expanding stent -- Microplane model; Biomedical engineering -- Periodicals; Medical instruments and apparatus -- Periodicals; 610.28
• DOI: 10.1177/0954411919865404
• Languages: English
• ISSNs: 0954-4119

Abstract

Transcatheter aortic valve implantation is a minimally invasive treatment for severe symptomatic aortic valve stenosis. Nitinol stents are proposed for aortic stenosis patients at high risk. In the present study, at different implantation depths in the aortic valve, the crimping and performance of Nitinol stents are investigated. To do so, a constitutive model based on Microplane theory is utilized and implemented through the finite element to express the constitutive characteristics of Nitinol. The self-expanding stent made of NiTi is designed and simulated using the finite element method. To validate the developed model, the obtained results using beam and solid finite element models are compared with those reported in the literature. Superelastic behavior as well as shape memory effect of the Nitinol stent is studied during crimping and deployment. The simulated results show that the produced radial force increases by increasing the implantation depth in a cardiac cycle.