主动脉覆膜支架对升主动脉的力学损伤机制研究

腔内主动脉修复术治疗累及弓部的主动脉夹层（AD）目前面临的主要难题之一是主动脉支架作用下的升主动脉损伤导致的支架相关新发破口。本研究假设支架过度弯曲引起的趋直现象是造成支架作用下升主动脉力学损伤的关键因素。本项目旨在研究主动脉支架的弯曲角度与支架作用下的升主动脉壁受力状态与损伤程度间的定性定量关系，阐释支架作用下的升主动脉壁力学损伤机制；探索通过植入分段式支架避免支架过度弯曲进而减小支架对主动脉壁力学损伤的可行性，提供减小主动脉支架作用下的升主动脉力学损伤的可能解决方案。通过非A非B型AD动物模型体内植入分段式或一体式支架后获取影像学、组织病理学、细胞学及分子生物学资料，结合力学分析模型建立支架弯曲角度与升主动脉壁受力状态及损伤程度间的函数关系。预期阐明支架过度弯曲是支架作用下主动脉力学损伤的机制、通过分段式支架治疗累及弓部的AD是减小升主动脉损伤的可能解决方案，具有重要的经济和社会价值。

By far, the main difficulty being confronted with endovascular repair of aortic dissection (AD) involved aortic arch is the injury of ascending aorta caused by stent graft (SG) and subsequent SG induced new entry (SINE). In this study, the straightening phenomenon caused by over bending of SG was hypothesized as the key factor of mechanical injury of ascending aorta. The aim of this project is to study the qualitative and quantitative relationships between the bending angle of SG, the stress state of ascending aortic wall , and the mechanical injury to ascending aortic wall under the mechanical action of SG, and to clarify the mechanism of mechanical injury to ascending aorta under the action of SG. The feasibility of reducing the mechanical injury of aortic wall by inserting segmental SG to avoid over bending will be explored and a possible solution to reduce the mechanical injury of ascending aorta under the action of aortic SG will be provided. The data of maging, histopathology, cytology and molecular biology will be obtained after the segmental or integrated SG implantation in non-A and non-B AD animal models. The functional relationship between the bending angle of the SG, the stress state and injury degree of the ascending aortic wall will be established with the mechanical analysis model. It is expected to clarify that the over bending of SG is the mechanism of mechanical injury of aorta under the action of SG, and the treatment of AD involved the arch by segmental SG is the possible solution to reduce the injury of ascending aorta. The study possess important economic and social values.