Personalised nitinol stent for focal plaques: Design and evaluation

Ran He,Liguo Zhao,Vadim V Silberschmidt,Jiling Feng,Ferdinand Serracino-Inglott

doi:10.1016/j.jbiomech.2021.110873

Abstract

The purpose of this study is to develop personalised nitinol stents for arteries with one and two opposite focal plaques. Novel designs are evaluated through comparison with a commercial stent design, in terms of lumen gain and shape as well as stress levels in the media layer after stenting. Methods: Personalised stents are developed for arteries with one and two opposite focal plaques, based on medical imaging of patients and computer simulations. In silico analysis is then carried out for assessment of stent performance in the diseased arteries. Results: Personalised designs significantly increase the lumen gain, reduce the stresses in the media layer, and improve the lumen shape compared to the commercial nitinol stent. Conclusion: The personalised designs show outstanding performance compared to the commercial stent. Significance: This pilot study proves that personalised nitinol stents are able to deliver desirable treatment outcomes.

Highlights

Self-expandable stents, made of nickel-titanium alloy, are used to treat atherosclerosis in femoropopliteal arteries
Compared to balloon angio plasty alone, the rate of arterial recoil and in-stent restenosis can be reduced by the self-expandable nitinol stents (Fusaro et al, 2013; Laird et al, 2010; Schillinger et al, 2006)
The disadvantages of the uniform stent design include over expansion of the healthy regions between the plaques as well as over expansion of the healthy side of the artery, which increase the risk of tissue damage, associated with instent restenosis

Summary

Introduction

Self-expandable stents, made of nickel-titanium alloy (nitinol), are used to treat atherosclerosis in femoropopliteal arteries. A three-parameter technique was proposed by Pant et al (2011, 2012) to optimise the design of a CYPHER stent, in order to improve its performance in terms of stent recoil, tissue stress, haemo dynamic disturbance, delivery and distribution of drug, and mechanical flexibility. They demonstrated that an improvement in one objective often came along with a compromise of other objectives. Designing personalised stent based on the lesion profile is potentially achievable with this approach, no promising results were produced by their designs

Objectives

Methods

Conclusion