In-stent restenosis

The luminal narrowing of arteries is a severe pathological condition that lead to hypoxia, ischemia and strokes. For the treatment of arterial narrowing, balloon-mounted stents are widely used. The long-term success of stents can be limited by the occurrence of in-stent restenosis. In the case of bare metal stents (BMSs), in-stent restenosis occurs in 20%-30% of cases within the first 6-9 months after stent replacement, requiring reoperation. In-stent restenosis is an excessive healing response which determine the re-narrowing of vessel wall. During stent expansion, high stresses induced by the balloon overpressure cause arterial injury, activating a cascade of inflammatory events inducing the pathological remodeling of arterial tissues.

In this framework, the current lack of appropriate experimental tools still limits the understanding of the onset and evolution of in-stent restenosis. On the other hand, in silico analyses of the stent-artery biomechanical system can support the medical research and the clinical practice for the long-term assessment of stent-based treatments of arterial narrowing. To reach this goal, this project aims to develop a computational tool for the modeling of the long-term success of stent deployment, with a special focus on both current and prospective approaches.

The project inherits several theoretical and computational challenges related to both material modeling and numerical implementation. The single ingredients that must be faced and coupled are:

• the constitutive modeling of arterial tissues;

• the modeling of damage in arterial tissues;

• the modeling of growth-and-remodeling in arterial tissues;

• the development of a chemo-mechano-biological multiphysics framework;

The project will allow to identify the dominant mechanisms driving in-stent restenosis, deciphering the role of the different molecular species in the pathological remodeling of arteries.

This project is carried out within the framework of the Masterplan SMART BIOTECS, alliance between the Technical University of Braunschweig and the Leibniz University of Hannover. This initiative is financially supported by the Ministry of Science and Culture (MWK) of Lower Saxony, Germany.