Drug-eluting vascular stents with surface modification of anticoagulation and pro-endothelialization

Abdominal aortic aneurysm (AAA) treatment relies on covered stents, yet thrombosis, restenosis, and delayed endothelialization remain challenges. This study developed a bifunctional heparin/zwitterionic polymer (CBMA) coating on dopamine-modified stents via surface-initiated atom transfer radical polymerization (SI-ATRP). The coating integrates CBMA's antifouling properties (98.5% reduction in BSA adsorption) with heparin's sustained anticoagulation (37% APTT prolongation, 17 s TT increase) and endothelialization promotion (194.97% endothelial cell activity after 5 days). Animal trials confirmed reduced TNF-α expression (75% decrease), enhanced collagen deposition, neovascularization post-28 days, and preserved mechanical strength (diametral tensile strength >57 MPa) with 25% lower permeability. This dual-functional coating offers a novel synergistic strategy for antithrombosis and endothelial repair in clinical applications.