小型猪冠状动脉置入过大直径支架建立再狭窄动物模型

A Restenosis Model Developed by Implantation of Oversized Stent inCoronary Arteries of Mini Swine

目的：用置入过大直径冠状动脉内支架的方法，在正常小型猪建立模拟人类冠状动脉再狭窄的实验动物模型。 方法：金属支架由３１６ Ｌ医用不锈钢丝编织而成，将不锈钢支架固定在３．０ ｍ ｍ 经皮冠状动脉腔内成形术（ＰＴＣＡ）球囊上，然后通过８ Ｆ大腔引导导管置入小型猪冠状动脉前降支中段，球囊与血管直径之比为１．１～１．３∶１。 结果：支架成功置入４只动物冠状动脉前降支中段。在支架置入后３个月重复冠状动脉造影显示：均发生再狭窄，平均管腔直径狭窄为（５５．８０±２３．０６）％ 。组织病理学结果显示：内弹力板撕裂，广泛新生内膜增生及严重管腔狭窄，平均新生内膜厚度和新生内膜面积分别为（１．０９±０．０６ ｍ ｍ ２ 和１．１８±０．３３ ｍ ｍ ２ ）。平均百分狭窄面积为（８６．８０±９．２４）％ 。 结论：①使用直径过大的球囊扩张型支架可成功地建立再狭窄动物模型。②该模型经济实用，其组织病理学表现与人类再狭窄结果十分相似。

Objective:To develop an experimental animal model that accurately mimics human coronary restenosis in normal mini swine by implantation of oversized intracoronary stent. Methods:The metallic stent was woven by 316L medical stainless steel.The stainless steel stents were mounted on 3 0mm percutaneous transluminal coronary angioplasty balloon.All stents were implanted into the middle segment of left anterior descending (LAD)through 8F large lumen guiding catheter,using oversized balloon inflated to 12 atm(The ratio of balloon to vessel diameter was 1 1～1 3∶1). Results:The stents were successfully implanted into the middle segment of LAD in 4 animals.After 3 months of stenting coronary angiogram showed that restenosis developed in all animals,mean diameter stenosis was(55 8±23 06)%.Morphometric analysis showed that fracture of internal elastic lamina,extensive neointimal proliferation and severe luminal stenosis.Mean neointimal thickness and neointimal area were (1 09±0 06 mm 2 and 1 18±0 33mm 2)respectively.Mean percent area stenosis was(86 80±9 24)%. Conclusions:①Restenosis animals model can be successfully produced by oversized stent.②This model is practical and inexpensive and closely mimics the proliferative portion of human restenosis.③It may be useful for understanding human restenosis and for testing therapies aimed at preventing restenosis after balloon angioplasty.