Histopathological Comparison among Biolimus, Zotarolimus and Everolimus-Eluting Stents in Porcine Coronary Restenosis Model

ABSTRACT

BACKGROUND AND OBJECTIVES: The aim of this study was to examine the histolopathogical effects among the biolimus, zotarolimus, and everolimus eluting stent (EES) in the porcine coronary restenosis model. SUBJECTS AND METHODS: Pigs were randomized into three groups in which the coronary arteries (15 pigs, 10 coronaries in each group) had either a biolimus A9 eluting stent (BES, n=10), zotarolimus eluting stent (ZES, n=10) or an EES (n=10). Histopathologic analysis was performed at 28 days after stenting. RESULTS: There were no significant differences in the injury score among the three groups. There was a significant difference in the internal elastic lamina, lumen area, neointima area, percent area stenosis, and the fibrin and inflammation score among the three groups (4.3+/-0.53 mm2, 2.5+/-0.93 mm2, 1.8+/-1.03 mm2, 40.7+/-20.80%, 1.7+/-0.41, 1.4+/-0.72 in the BES group vs. 5.1+/-0.55 mm2, 2.3+/-1.14 mm2, 2.8+/-1.00 mm2, 55.4+/-21.23%, 2.0+/-0.39, 1.6+/-0.76 in the ZES group vs. 4.4+/-0.53 mm2, 1.7+/-1.22 mm2, 2.8+/-1.23 mm2, 64.0+/-26.00%, 1.8+/-0.76, 2.1+/-0.90 in the EES group, respectively). BES is more effective in inhibiting neointimal hyperplasia compared to ZES and EES (p<0.0001). According to the fibrin and inflammation score, BES and EES are more effective in decreasing the fibrin deposition compared to ZES (p<0.001). Moreover, BES and ZES are more effective in reducing the inflammatory reaction compared to EES (p<0.001). CONCLUSION: The result demonstrates that BES shows better histopathological characteristics than ZES and EES at one month after stenting in the porcine coronary restenosis model.