生物全降解药物支架植入小型猪冠状动脉：安全性及组织相容性

背景：为解决聚左旋乳酸支架支撑力不足、代谢的酸性产物容易导致血管局部无菌性炎症等缺点，本课题组设计出新型支架，在聚左旋乳酸基础上融入无定型磷酸钙纳米颗粒。目的：评价新型生物全降解支架聚左旋乳酸/无定型磷酸钙纳米颗粒的安全性及组织相容性。方法：取16头健康西藏小型猪，随机选取左前降支、左回旋支或右冠状动脉支相同管腔大小的血管段，植入新型生物全降解支架1枚，于植入前、植入后1个月取股动脉血标本，行血液学检测。植入1，6个月后，复查冠状动脉造影后对支架段标本行苏木精-伊红染色，观察支架血管损伤、炎症及内皮化程度。结果与结论：支架植入前后血常规、血生化指标无明显变化。支架植入1，6个月后，冠状动脉造影提示冠状动脉通畅，无血栓形成，支架段血管与周围组织界限清楚，无组织粘连、坏死、贴壁不良等异常表现。与支架植入1个月时比较，植入6个月后的炎症积分降低（P 〈0.05）、内皮化积分增加（P 〈0.05），植入部位损伤积分无明显变化；并且支架周围未见心肌梗死灶及炎性细胞浸润。结果表明新型生物全降解支架具有良好的安全性及组织相容性。

Safety and histocompatibility of a novel biogradable stent implanted into the coronary artery in a porcine model

BACKGROUND：In order to solve the problems of poly-l-lactic acid （PLLA） stents, such as poor support, acidic metabolites, we researched a novel biogradable stent-PLLA/amorphous calcium plosphate （ACP）. OBJECTIVE： To discuss the safety and histocompatibility of the novel biogradable stent-PLLA/ACP stent implanted in the coronary artery in a porcine model. METHODS：Sixteen novel biogradable stents were randomly implanted into the coronary arteries, left anterior descending branch, left circumflex artery or right coronary artery of sixteen healthy Tibet miniature pigs. The blood routine and blood biochemistry were measured pre-operation and at 1 month after operation. The coronary blood vessels where the stent was implanted were examined by hematoxylin-eosin staining at 1 and 6 months after operation. RESULTS AND CONCLUSION： Compared with pre-operation, the post-operation indicators of the blood routine and blood biochemistry were of no significant difference. Coronary angiography revealed coronary artery patency and no thrombosis, the vascular stent segments exhibited clear boundaries with the surrounding tissue, with no tissue adhesion, necrosis, and adherence abnormalities. The results of hematoxylin-eosin staining showed that there was no significant difference in vascular injury integral between 1 month after operation and 6 months after operation. However, 6 months after operation, the scores of the inflammation were lower （P 〈 0.05）, and the scores of the endothelialization were increased （P 〈 0.05）. There was no myocardial infarction and inflammatory cellinfiltration around the stent. These results suggest that the novel biodegradable stent has good safety and histocompatibility.