Ponente
Descripción
Drug-eluting stents are widely employed to reduce restenosis following coronary angioplasty by locally delivering antiproliferative drugs to the arterial tissue. This work presents a mathematical and computational model for the transport of sirolimus released from the polymer coating of an annular stent into a multilayer arterial wall. The computational domain is represented by a two-dimensional axisymmetric geometry containing the stent strut, the drug-loaded polymer coating, and the arterial wall. The wall is divided into the intima, media, and adventitia, while the endothelium, internal elastic lamina, and external elastic lamina are represented as thin semipermeable membranes separating the corresponding tissue regions.
The polymer coating is considered the initial sirolimus reservoir, and drug transport through the coating and arterial tissues is described using transient transport equations with domain-dependent diffusivities and interface transmission conditions. The membrane conditions account for discontinuities in concentration and resistance to mass transfer between adjacent arterial layers. The governing equations are discretized using the Galerkin finite element method on an unstructured triangular mesh. The numerical formulation is implemented in the Julia programming language using the Gridap finite element library.
The proposed framework provides the spatial and temporal distributions of sirolimus concentration within the polymer coating and the different arterial layers. It also enables evaluation of how heterogeneous tissue properties and membrane resistances influence drug penetration, retention, and distribution following stent implantation. The model constitutes a computational tool for studying drug-eluting stent performance and supporting the optimization of polymer coatings and drug-release strategies.