Fluid-Structure Interaction in Coronary Stents: A Discrete Multiphysics Approach

Abstract

Stenting is a common method for treating atherosclerosis. A metal or polymer stent is deployed to open the stenosed artery or vein. After the stent is deployed, the blood flow dynamics influence the mechanics by compressing and expanding the structure. If the stent does not respond properly to the resulting stress, vascular wall injury or re-stenosis can occur. In this work, a Discrete Multiphysics modelling approach is used to study the mechanical deformation of the coronary stent and its relationship with the blood flow dynamics. The major parameters responsible for deforming the stent are sorted in terms of dimensionless numbers and a relationship between the elastic forces in the stent and pressure forces in the fluid is established. The blood flow and the stiffness of the stent material contribute significantly to the stent deformation and affect its rate of deformation. The stress distribution in the stent is not uniform with the higher stresses occurring at the nodes of the structure. From the relationship (correlation) between the elastic force and the pressure force, depending on the type of material used for the stent, the model can be used to predict whether the stent is at risk of fracture or not after deployment.

3D computational fluid dynamics of Newtonian and non-Newtonian blood flow in coronary arteries with implanted stents

“…This similarity and conditions are also confirmed by reference [44]. The shape of the velocity profiles for different flow models in a smooth vessel can be compared with references [42,50,52,53,55].…”

“…as seen in Equation 9and Table 2, the maximum value of viscosity in the non-Newtonian power-law model is equal to the viscosity of the Newtonian model, which indicates that it is not allowed to advance more than that value. The shape of velocity profiles for different flow models in a smooth vessel can be compared with references [42,50,[52][53][54][55].…”

“…In Table 1, the geometric parameters of our problem are given. The modeled stent geometry for our problem is also shown in Figure 2 (geometry is similar to reference [42]). The designed stent is drawn in a Solid-Work.…”

Simulating the Hydrodynamic Conditions of the Human Ascending Colon: A Digital Twin of the Dynamic Colon Model

“…This creates a lattice structure that replicates the properties of an elastic solid [35]. This approach has been used previously to model biological membranes [25,38]. The Hookean coefficient used for the lattice is k M,b , the coefficient used for the tethered springs is k M,p .…”

Development of a digital twin of a tablet that mimics a real solid dosage form: Differences in the dissolution profile in conventional mini-USP II and a biorelevant colon model

“…This study uses a simulation technique called Discrete Multiphysics (DMP) (Alexiadis, 2015(Alexiadis, , 2014. DMP is a mesh-free technique that uses computational particles instead of computational grids and has been successfully used to model human organs: Ariane et al (2017aAriane et al ( , 2018aAriane et al ( , 2018bAriane et al ( , 2017b, Baksamawi et al (2021), Mohammed et al (2020Mohammed et al ( , 2021, Alexiadis (2015bAlexiadis ( , 2015aAlexiadis ( , 2019, Alexiadis et al (2017), and Schütt et al (2021, 2022. It couples particle-based methods such as Smoothed Particle Hydrodynamics (SPH), Lattice Spring Model (LSM), and Discrete Element Method (DEM) and Peridynamics (Sanfilipo et al, 2021).…”