Department of Radiology, First Affiliated Hospital of China Medical University, Key Laboratory of Diagnostic Imaging and Interventional Radiology, Liaoning Province.
J Endovasc Ther. 2011 Jun;18(3):407-15. doi: 10.1583/10-3353.1.
To determine the efficacy of sirolimus-eluting bioabsorbable magnesium alloy stents (SEBMAS) in restenosis prevention.
A balloon-expandable bioabsorbable magnesium alloy stent (BMAS) was created and coated with biodegradable poly(lactic acid-co-trimethylene carbonate) that contained the antiproliferative drug sirolimus (140 ± 40 µg/cm²). Both the uncoated BMAS and the coated SEBMAS were deployed 2 cm apart in balloon-injured infrarenal abdominal aortas of 20 New Zealand white rabbits. The stented aortic segments were removed at 30, 60, 90, and 120 days (5 rabbits per interval) after implantation. The average stent strut sectional area of each group was measured to evaluate the degree of magnesium corrosion and to forecast the biodegradation time profile of the magnesium stent. Histology and histopathology of the sectioned stented aortic segments were performed to evaluate neointima formation, endothelialization, and inflammation.
The SEBMAS degraded gradually after being implanted into the rabbit aorta, and total biocorrosion occurred after ~120 days. In all groups, the lumen area was significantly greater, but the neointimal area was significantly smaller in SEBMAS segments compared with the uncoated BMAS segments (p < 0.05) at all time points. There was no significant difference in the injury or inflammation scores between the groups. Endothelialization was delayed at 30 days in the SEBMAS segments vs. the uncoated BMAS segments.
SEBMAS further reduces intimal hyperplasia and improves the lumen area when compared to uncoated BMAS; however, it delays vascular healing and endothelialization.
评估西罗莫司洗脱可生物吸收镁合金支架（SEBMAS）在预防再狭窄方面的疗效。
制作了一种球囊扩张可生物吸收镁合金支架（BMAS），并在其表面涂覆了含有抗增殖药物西罗莫司（140 ± 40 µg/cm²）的可生物降解聚（乳酸-co-三亚甲基碳酸酯）。将未涂层的 BMAS 和涂层的 SEBMAS 分别在 20 只新西兰白兔的腹主动脉损伤部位进行 2 cm 间隔部署。在植入后 30、60、90 和 120 天（每组 5 只兔子）时取出支架的主动脉段。测量每组支架的平均支架支柱截面积，以评估镁腐蚀的程度，并预测镁支架的生物降解时间曲线。对分段支架主动脉段进行组织学和组织病理学检查，以评估新生内膜形成、内皮化和炎症情况。
SEBMAS 植入兔主动脉后逐渐降解，约 120 天后完全生物腐蚀。在所有时间点，SEBMAS 段的管腔面积明显大于未涂层的 BMAS 段，但新生内膜面积明显小于后者（p < 0.05）。各组之间的损伤或炎症评分无显著差异。与未涂层的 BMAS 段相比，SEBMAS 段在 30 天时内皮化延迟。
与未涂层的 BMAS 相比，SEBMAS 进一步减少了内膜增生，增加了管腔面积；然而，它延迟了血管愈合和内皮化。
