Microneedle Stent for Intravascular Anchoring Effect

Cardiovascular diseases remain the leading cause of death worldwide, largely due to sudden blockage or narrowing of coronary arteries, with myocardial infarction and angina as common outcomes. Stent implantation is a widely used intervention to restore vessel patency, offering advantages such as reduced invasiveness, faster recovery, and improved patient comfort compared to surgery. However, complications including in-stent restenosis, elastic recoil, and stent migration persist. Among these, stent dislodgement poses a particularly severe risk, underscoring the need for improved anchoring strategies. Microneedles (MNs), recognized for their minimal invasiveness and strong tissue-fixation capability, present an attractive but unexplored approach for vascular stents. Here, we report a novel microneedle stent (MNS) in which MN arrays were conformally integrated onto the surface of a 3D-printed polycaprolactone stent using a UV-curable resin transfer-molding process. The MNs exhibited high structural fidelity, tunable mechanical strength, and stable adhesion to the stent surface, governed by UV-crosslinking conditions. In vitro flow studies using a vessel phantom and peristaltic pump demonstrated robust anchoring under physiological conditions. Furthermore, in vivo implantation confirmed enhanced vascular fixation without adverse inflammatory responses. This work represents the first integration of MNs into vascular stents, offering a promising strategy to improve stent stability and clinical outcomes.