Background In-stent restenosis is caused by neointimal hyperplasia, which involves abnormal growth of vascular smooth muscle cells (VSMC). Zedoray constituents is known to inhibit smooth muscle cell hyperplasia and migration, while inhibit ADP induced platelet aggregation.

Objective To evaluate the biological characteristics of stents coating with zedoray constituents in porcine coronary model.

Methods Bare metal stents (BMS, n=36), Sirolimus eluting stents (SES, n=36) and Zedoray eluting stents (ZES, n=36) were implanted in the proximal segment of three different epicardial coronary arteries in 36 swines randomly. Coronary angiography, optical coherence tomography (OCT) and histomorphologic analysis were performed at 30 days and 90 days after the procedure.

Results The 30 day (n=24) OCT examination showed ZES arm has larger lumen diameter (LD), acceptable mean lumen stenosis of area (MSA) compared with BMS (LD: ZES 1.9±0.51 mm, SES 1.85±0.41 mm, BMS 1.1±0.3 mm, p<0.05; MSA%: ZES 21.7±19.3, SES 23.2±18.9 BMS 41.7±21.3, p<0.001). By histomorphomeric analysis, similar injury scores were observed at the three arms (p>0.05). However, significant inflammation score reduction was seen in ZES group (ZES: 0.65±0.54, SES: 1.03±0.44, BMS: 0.94±0.75, p<0.001) compared to other two groups at 30 day, no differences in three groups at 90 day. Either at 30 day or 90 day, by qualitative analysis, well developed endothelium was seen in ZES arm, while impaired endothelium was observed with part of stent strut naked at vessel lumen at SES arm.

Conclusion Zedoray eluting stents can reduce neointimal hyperplasia with good endothelia coverage in porcine coronary model.