摘要
对自膨胀式镍钛记忆合金颈动脉支架进行了体外加速腐蚀疲劳实验。实验模拟了人体血管内的受力、温度和腐蚀环境,对部分支架还增加模拟了颈动脉弯曲造成的对支架径向的扰动。经过4亿次脉动的加速疲劳实验,支架径向支撑强度没有减弱;实验结束后支架的形态、外部结构完整。径向回缩小于5%,轴向回缩小于6%;扫描电镜微观检查,支架金属表面没有腐蚀疲劳的痕迹;施加扰动的支架与未施加扰动的支架没有明显差异。
The fatigue propertise of self-expanding nitinol carotid stent was studied in an in vitra accelerating test set up in which the condition simulated the human environments in hemodynamics, temperature and corrosion. Part of the stents tested were bended periodically in radial direaction as disturbance during the testing procedures. Radial outward loads on the stents were monitored, during the test. Morphology and structure of the stents were observed by SEM, after the test end, and recoil percentage for balloon expandable stents were also recorded. Experimental results indicated radial outward load on the stents retained constant during the test. The SEM photos showed that morphology and structure of all stents tested were integrated and corrosive traces were not found in the metallic surface of the tested stents. The radial recoil for tested stents were less than 5% , and the axis recoil were less than 6%. There were not significantly differences between disturbance and non-disturbance stents. This experiment demonstrated that tested Nitinol carotid stent had an excellent fatigue resistance.
出处
《北京生物医学工程》
2007年第1期78-80,83,共4页
Beijing Biomedical Engineering
