316L不锈钢和NiTi合金血管支架的血液相容性

Blood compatibility of 316L stainless steel and NiTi alloy vascular stent

学术背景:临床广泛使用的316L不锈钢、NiTi合金血管支架,有较好的耐腐蚀性和血液相容性。但随着人们对这两种材料血液相容性的深入研究,也发现了它们在血液中有离子渗出、表面血栓等问题,如何提高316L、NiTi合金血管支架的血液相容性已成为人们研究的重要课题。目的:介绍316L不锈钢、NiTi合金血管支架血液相容性研究现状,探讨金属支架表面生物化处理的方向。检索策略:应用计算机检索PubMed数据库、Science Direct数据库和中文科技期刊CNKI数据库1996-01/2007-09的相关文章,检索词为"NiTi合金血管支架、316L血管支架、表面改性、血液相容性",限定文章语言种类为中文和英文。共检索到论文1759篇,其中英文909篇,中文850篇。纳入标准:①与NiTi合金、316L不锈钢有关的表面改性、血液相容性研究。②材料表面因素与蛋白吸附、血液相容性关系。剔除内容重复性的研究,并以近3年文献为主,最终确定了33篇。文献评价:在确定的文献中,关于316L、NiTi合金血管支架应用中存在血栓问题的文献6篇,腐蚀问题的文献6篇,影响材料抗凝血性表面因素的文献8篇,提高316L、NiTi合金支架血液相容性途径的文献13篇。资料综合:现用的血管支架材料316L、NiTi合金在血液中仍有离子析出、血栓产生。通过降低材料表面的粗糙度,改变生物材料表面化学成分和化学组成,使材料表面呈负电性,降低材料表面的张力与表面能几方面因素提高血管支架材料316L、NiTi合金的血液相容性。结论:在没有开发出新的血管支架材料前,对现有支架材料316L、NiTi合金表面进行生物化改性处理是提高支架血液相容性的一条途径。

BACKGROUND： The 316L stainless steel and NiTi alloy vascular stent widely used in clinic have good corrosion resistance and blood compatibility. But with the further study on these two kinds of material in blood compatibility, their problems such as ions release, surface thrombus and so on are found. How to improve these materials＇ blood compatibility has become an importance project. OBJECTIVE： To introduce the current study of the blood compatibility of 316L stainless steel and NiTi alloy vascular stent, and investigate the research directions of bioprocessing on the metallic stent＇s surface. RETRIEVAL STRATEGY： The relevant articles from January 1999 to September 2007 were retrieved from the PubMed, Science Direct and China National Knowledge Infrastructures by using the key words of ＂surface modification, blood compatibility, 316L stainless vascular steel, NiTi alloy vascular stent＂. And the languages were limited to English and Chinese. A total of 1759 literatures were retrieved, including 909 English literatures and 850 Chinese literatures. Inclusive criteria：①the relevant literatures on the surface modification and the blood compatibility of the NiTi alloy and 316 stainless steel.②the material surface factors on the protein adsorption and the blood compatibility. Repetitive articles were excluded, and literatures in recent three years were mainly selected. At last 31 literatures were collected. LITERATURE EVALUATION： Among the colleted articles, six of them were about the thrombogenesis, six about the corrosion, eight about the surface factors influencing the anticoagulant property of materials, and 13 about the way of increasing blood compatibility of materials. DATA SYNTHESIS： The existing 316L and NiTi alloy vascular stent still release ions and negerate thrombogenesis in blood. The blood compatibility of metallic stent would be improved by decreasing surface rugosity, altering chemical composition on surface, inducing electronegation of material surface, and reducing surface tension and energy. CONCLUSION： Before the new vascular stent material is invented, bio-modification treatment on 316L and NiTi alloy surface is a way to improve the blood compatibility of metallic stents.