Mechanistic evaluation of long-term in-stent restenosis based on models of tissue damage and growth

Abstract

Development and application of advanced mechanical models of soft tissues and their growth represent one of the main directions in modern mechanics of solids. Such models are increasingly used to deal with complex biomedical problems. Prediction of in-stent restenosis for patients treated with coronary stents remains a highly challenging task. Using a finite element method, this paper presents a mechanistic approach to evaluate the development of in-stent restenosis in an artery following stent implantation. Hyperelastic models with damage, verified with experimental results, are used to describe the level of tissue damage in arterial layers and plaque caused by such intervention. A tissue-growth model, associated with vessel damage, is adopted to describe the growth behaviour of a media layer after stent implantation. Narrowing of lumen diameter with time is used to quantify the development of in-stent restenosis in the vessel after stenting. It is demonstrated that stent designs and materials strongly affect the stenting-induced damage in the media layer and the subsequent development of in-stent restenosis. The larger the artery expansion achieved during balloon inflation, the higher the damage introduced to the media layer, leading to an increased level of in-stent restenosis. In addition, the development of in-stent restenosis is directly correlated with the artery expansion during the stent deployment. The correlation is further used to predict the effect of a complex clinical procedure, such as stent overlapping, on the level of in-stent restenosis developed after percutaneous coronary intervention.

A homogenized constrained mixture model of restenosis and vascular remodelling after balloon angioplasty

“…The predicted outward remodelling in the iliac model is initially due to the loss of collagen and elastin. However, the outer radius keeps increasing after stabilization of these respective densities owing to the continuous update of collagen stretch, which is impossible to predict with a kinematic growth model as used in previously developed finite-element models of restenosis [18,19,38]. This is the main advantage associated with the use of the constrained mixture model.…”

“…Fereidoonnezhad et al [18] presented a kinematic growth model, where the overall growth of the wall is based on a certain overloading level, and a subsequent mass increase after balloon angioplasty, inspired by Schwartz et al [8]. He et al [19] use a similar approach, but include tissue damage in the form of a Mullins effect and include balloon, stent and plaque geometries in their idealized model. Escuer et al [20] present a twodimensional axisymmetric finite-element model of tissue growth after stent implantation, taking into account multiple aspects of an inflammation reaction mechanism.…”

From the real device to the digital twin: A coupled experimental-numerical strategy to investigate a novel bioresorbable vascular scaffold

“…In particular, the topic of interest focuses on how to develop a reliable finite element model of a commercial bioresorbable polymeric stent, being available only a few samples of the device and no information on the material, which in this case is Tyrocore TM . This condition has to be faced when, for example, a clinician or a company wants to perform an independent study, for clinical planning or comparison purposes, respectively [ 17 , 35 – 37 ]. A strategy, that involves the coupling of selected experimental and numerical activities, has been proposed to investigate and correctly simulate the mechanical response of the bioresorbable coronary delivery system.…”

Percutaneous Coronary Intervention of a Diffusely Degenerated Saphenous Vein Graft: A Road Less Taken

“…Therefore, the production of ISR during stent deployment is directly related to the magnitude of artery expansion. 19 He et al 19 created a tissue-growth model, which compares the stent-induced tissue damage with the ISR and using the finite-element method to simulate ISR creation after PCI.…”