Corrosion Fatigue Resistant and Intimal Hyperplasia Suppressive Biometal for Bioabsorbable Stents

摘要 心脏病因其对工业化国家健康的巨大影响而引起社会的极大关注 国家，特别是在肥胖率很高、典型饮食是 不利于心血管健康。虽然侵入性手术并不可取，但它们是可取的 通常对确保病人的生存至关重要。全世界共植入了500万个冠状动脉支架- 在患者的一生中，每年都会出现在人体动脉中。这有 导致出现了几种严重的副作用。一种生物可吸收金属支架， 随着时间的推移，无害的侵蚀可以将与以下因素相关的正常慢性风险降至最低 永久性支架。 我们的实验室一直致力于改进可生物降解材料的组成和微观结构 并测试它们在过去四年中在血管环境中的行为 多年来致力于开发一种具有机械性能和生物兼容性的金属， 血管内支架的应用。对科学理解做出了巨大贡献 在锌基体系中，我们现在准备开发更复杂的锌基合金，2-3 符合生物可降解支架基准值的合金元素，包括：1) 卓越的耐腐蚀疲劳性，可消除早期(6至9个月)断裂 生物可降解支架(镁基和锌基支架中的常见问题 几年)；2)将体内腐蚀速率维持在接近0.02毫米/年的值；3)展示 &gt；200兆帕屈服强度和25%-30%的断裂伸长率；以及4)演示 在短期和长期炎症反应、再内皮化、 和抑制内膜增生，与316L不锈钢相似或更好(工业 支架材料的标准)。

Summary Heart disease is of great societal interest due to its drastic impact on health in industrialized nations, especially in developed countries where obesity rates are high and the typical diet is not conducive to cardiovascular health. While invasive procedures are not desirable, they are often crucial to ensuring patient survival. The five million coronary stents administered world- wide each year remain present in the human artery for the lifetime of the patient. This has resulted in the emergence of several serious side effects. A bioabsorbable metal stent that harmlessly erodes away over time could minimize the normal chronic risks associated with permanent stents. Our laboratory has been working to refine the composition and microstructure of biodegradable Zn-based binary alloys and test their behavior in the vascular environment over the last four years in an effort to develop a metal with mechanical properties and biocompatibility required for endovascular stent applications. Having contributed enormously to the scientific understanding of Zn-based systems, we are now ready to develop more complex Zn-based alloys with 2-3 alloying elements that meet benchmark values for biodegradable stents, including: 1) have superior corrosion fatigue resistance that eliminates early stage (6 to 9 months) fracturing of biodegradable stents (common problem in Mg-based and Zn-based stents prototyped in the last several years); 2) maintain in vivo corrosion rates close to the 0.02 mm/year value; 3) exhibit >200 MPa yield strength, and >25-30% elongation to failure; and 4) demonstrate biocompatibility in terms of short- and long-term inflammatory responses, re-endothelialization, and suppressed intimal hyperplasia, similar or better than 316L stainless steel (industrial standard for stent materials).