Auxetic Stents as a Next Generation Solution for Vascular Diseases-A Review.

OBJECTIVE: Vascular diseases, particularly atherosclerosis, represent a leading cause of global morbidity and mortality. Endovascular stenting has emerged as a cornerstone of therapy to restore vessel patency, yet conventional stents remain obstructed by significant clinical limitations, including in-stent restenosis, thrombosis, and mechanical failure. These adverse outcomes are intrinsically linked to their fundamental structural design, which is characterized by a positive Poisson's ratio, leading to foreshortening and a biomechanical mismatch with the native vasculature.

METHODS: This review critically examines auxetic stents as a next-generation solution, engineered with a structure possessing a negative Poisson's ratio. This unique property allows them to expand axially upon radial deployment, thereby eliminating foreshortening, enhancing conformability to tortuous vessels, and distributing mechanical stress more uniformly onto the arterial wall.

RESULTS: This paper synthesizes the robust body of in-silico/bench-top evidence from computational modeling and in-vitro experimentation that validates these superior biomechanical characteristics. Furthermore, it explores the profound and favorable biological implications, arguing that the optimized mechanical environment and improved hemodynamics are hypothesized to attenuate the primary triggers for neointimal hyperplasia and foster rapid, complete endothelialization.

CONCLUSION: The review concludes by outlining the translational pathway, including challenges in structure integration and discussing the vast future horizons for auxetic structured stents in complex peripheral, carotid, and non-vascular applications. Auxetic design represents a paradigm shift from material-centric iteration to structure-driven innovation, holding the promise to significantly improve the long-term safety and efficacy of endovascular stent implants.