Biomimetic CD31-coated stent maintains physiological performance under high barotrauma in pigs

Drug-eluting stents (DES) have largely solved late thrombosis in most PCI patients. The remaining challenge concerns those at high bleeding risk (HBR, 30–40%), where balancing ischemic and bleeding events remains unresolved. Safely shortening dual antiplatelet therapy (DAPT) is now a key unmet need. For a novel stent to tolerate reduced DAPT, it must resist early thrombogenic triggers and promote rapid endothelial recovery. High-barotrauma implantation (balloon-to-artery ratio >1.3) induces severe vascular injury and delayed healing, forming a stringent preclinical model. A novel CD31 endothelial-mimetic coating based on SP1072, a 16-amino-acid peptide reproducing a key motif of CD31 domain 1 mediating homophilic interactions governing blood homeostasis, provides a biomimetic surface restoring anti-thrombo-inflammatory signaling without drug elution.

To evaluate, by quantitative coronary angiography and OCT, the mechanical and physiological performance of an SP1072-coated cobalt–chromium stent compared with an everolimus-eluting stent (Xience, Abbott Vascular, USA) in a porcine coronary model under deliberate high barotrauma.

Twelve CD31-coated and six DES were implanted in the LAD, LCX, and RCA of eight pigs (mean BAR >1.3). Quantitative coronary angiography (QCA), fractional flow ratio (µFR), OCT-derived FFR (OFR), and volumetric OCT analyses were performed at baseline and one month.

At implantation, BAR averaged 1.33 ± 0.20 (CD31) vs 1.34 ± 0.09 (DES); acute recoil was higher for CD31 (6.0 ± 1.6 % vs 3.2 ± 2.2 %, p = 0.02). After one month, MLD (2.21 ± 0.48 mm vs 2.20 ± 0.47 mm), % diameter stenosis (23.5 ± 12.3 vs 18.6 ± 13.5), µFR (0.94 ± 0.08 vs 0.96 ± 0.03), and OFR (0.94 ± 0.07 vs 0.96 ± 0.03) were comparable. OCT confirmed complete strut coverage and no thrombus or malapposition. Minimum stent area (4.71 ± 1.58 mm² vs 3.57 ± 1.77 mm², p = 0.26) and mean lumen area (5.60 ± 1.45 mm² vs 4.76 ± 1.75 mm², p = 0.38) were numerically higher for CD31, while neointimal volume (37.9 ± 21.3 mm³ vs 28.1 ± 5.6 mm³, p = 0.20) and stent volume (122.3 ± 18.2 mm³ vs 98.5 ± 26.3 mm³, p = 0.12) were greater.

Even under extreme mechanical stress known to delay endothelial recovery, the CD31-coated stent preserved lumen geometry and flow comparable to a DES while achieving complete endothelial coverage without drug release. Higher minimum stent and mean lumen areas suggest maintained expansion and limited neointimal growth despite the absence of antiproliferative drug. These findings indicate that the CD31 coating preserves mechanical integrity and vascular compatibility even in a stringent injury model, warranting further evaluation under standard implantation (BAR ≈ 1.05) and high-bleeding-risk conditions. By promoting rapid vascular healing without an antiproliferative agent, this biomimetic approach may represent a path toward safer DAPT de-escalation in interventional cardiology.