Skirball Center for Cardiovascular Research for Cardiovascular Research Foundation, 8 Corporate Dr., Orangeburg, New York, NY 10965, USA.
Atherosclerosis. 2010 Dec;213(2):518-24. doi: 10.1016/j.atherosclerosis.2010.09.021. Epub 2010 Sep 25.
To date, most of all new developments in stent technologies are tested in normal animals. Although invaluable in the evaluation of device safety, the juvenile domestic swine (DS) do not follow the biological healing response occurring in humans following coronary stent implantation. By using a novel swine breed afflicted with familial hypercholesterolemia (FHS), we aimed to analyse the vascular response occurring following bare metal stent (BMS) implantation by comparing in vivo endovascular imaging and histological data.
A total of 26 swine were included in this study (12 FHS and 14 DS). Sixty eight BMS (FHS=28 versus DS=40) were implanted using a 10% overstretch ratio. Imaging evaluation (IVUS and OCT) was conducted in all animals at 30 (n=14) or 90 (n=12) days following stent implantation. After imaging, the stented coronary segments were harvested for histological evaluation.
At 30 days, the degree of neointimal formation analysed by OCT (%AS=DS 21.9 ± 10% versus FHS 25.4 ± 12%; p=0.18) and histology (DS 24.6 ± 10% versus FHS 23.58 ± 10%; p=0.8) was similar between both animal groups. At 90 days, the degree of neointimal formation in the DS group decreased in all analysed variables (-40% in IVUS neointimal volume, -57% in OCT %AS, and -30% in %AS by histology) compared to the progression of neointimal formation observed in the FHS group (+29% in IVUS neointimal volume, +27% in OCT %AS and +43% in %AS by histology).
The pattern of neointimal formation following BMS implantation in the FHS follows a progressive course that does not occur in the DS. Therefore, by providing a progressive neointimal biological response to BMS implantation, the FHS could serve as an ideal efficacy model for the validation of drug eluting stent technologies.
迄今为止，支架技术的大多数新进展都是在正常动物身上进行测试的。尽管在评估器械安全性方面具有重要价值，但幼年家猪（DS）并不能反映出人类在冠状动脉支架植入后的生物愈合反应。本研究采用一种新型患有家族性高胆固醇血症（FHS）的猪种，旨在通过比较血管内超声（IVUS）和光学相干断层扫描（OCT）成像与组织学数据，分析裸金属支架（BMS）植入后的血管反应。
本研究共纳入 26 只猪（12 只 FHS 和 14 只 DS）。共植入 68 枚 BMS（FHS=28 枚，DS=40 枚），扩张比为 10%。所有动物在支架植入后 30（n=14）或 90 天（n=12）时进行 IVUS 和 OCT 成像评估。成像后，对支架血管段进行组织学评估。
30 天时，OCT 分析的新生内膜形成程度（%AS=DS 21.9±10%，FHS 25.4±12%；p=0.18）和组织学分析的新生内膜形成程度（DS 24.6±10%，FHS 23.58±10%；p=0.8）在两组动物之间相似。90 天时，与 FHS 组新生内膜形成的进展相比，DS 组的所有分析变量（IVUS 新生内膜体积减少 40%，OCT %AS 减少 57%，组织学分析的%AS 减少 30%）均呈下降趋势。
FHS 猪种在 BMS 植入后的新生内膜形成模式呈进展性，而 DS 猪种则不会出现这种情况。因此，FHS 可作为一种理想的药物洗脱支架技术验证的疗效模型，因为它对 BMS 植入后呈现出逐渐的新生内膜生物反应。
