Digital twin-enabled cardiovascular stent optimization: a virtual reality-driven approach to mitigate...

Percutaneous transluminal angioplasty with stenting is extensively applied for treatment of atherosclerosis. However, the effects of dogboning (d_b), foreshortening (f_s), longitudinal recoil (l_r) and radial recoil (R_r) usually occur to inflict damage to the artery and make the positioning difficult during the cardiovascular stent (CS) expansion to the maximum and after the inflated balloon removing. In the article, the design and manufacture of a CS were carried out based on digital twin (DT) technology rather than traditional expertise- and experience-based methods. The highly kinetic model of a CS was firstly derived from its upfront proposed geometric configuration, governing equations of solid mechanics and boundary conditions to construct its DT through virtual reality (VR). Then global sensitivity analysis (GSA) and dynamic response optimization (DRO) was implemented to optimize the material and processing parameters including Young's modulus (E), isotropic tangent modulus (E_t), Poisson's ratio (ν), density (ρ) and initial yield stress (σ), in order to obtain a satisfied behavior requirements for effects of d_b, f_s, l_r and R_r. The prototype experiment result showed that the CS made of shape memory Nitinol with optimal material and processing parameters (ρ = 7050 kg m^-3, ν = 0.27, E = 205 GPa, E_t = 675.13 MPa and σ = 198.49 MPa) obtained from its digital twin through VR simulation could have desired behavior performance characteristics, such as weak effect of d_b and f_s during the CS expansion to the maximum, and l_r (-0.9%), distal R_r (0.4%) and central R_r (0.7%) after the inflated balloon removing.