In Situ H2S-Releasing Stents Optimize Vascular Healing.

Stent implantation remains a cornerstone of interventional cardiology, providing a minimally invasive solution to restore blood flow in occluded vessels. However, current stents face persistent challenges in simultaneously preventing neointimal hyperplasia and promoting reendothelialization, compromising their long-term efficacy. To address these limitations, we developed an in situ H2S-releasing polymer brush-coated stent that actively modulates material-blood interactions, creating a favorable microenvironment for vascular healing. H2S enhances the stent's antithrombotic properties by inhibiting fibrinogen binding and platelet activation, while also mitigating oxidative stress and promoting macrophage polarization toward the anti-inflammatory M2 phenotype. In vivo, the H2S-releasing stents significantly improved vascular healing by accelerating endothelialization and inhibiting smooth muscle cell overproliferation, resulting in a thinner neointima with functional endothelial coverage. Transcriptomic analysis further elucidated the underlying mechanisms, revealing H2S-mediated modulation of key biological pathways that support vascular healing. These findings underscore the potential of in situ H2S release as an effective strategy for optimizing vascular implants and improving long-term outcomes.