Research of Customized Aortic Stent Graft Manufacture

[摘要] Thoracic descending aorta diseases include aortic dissection and aortic aneurysm, of which the natural mortality rate is extremely high. At present, endovascular aneurysm repair (EVAR) has been widely used as an effective means for the treatment of descending aortic disease. Most of the existing coating stents are standard design, which are unable to meet the size or structure of different patients. As a result, failure of treatment would be caused by dimensional discrepancy between stent and vessels, which could lead to internal leakage or rupture of blood vessels. Therefore, based on rapid prototyping sacrificial core - coating forming (RPSC-CF), a customized aortic stent graft manufactured technique has been proposed in this study. The aortic stent graft consists of film and metallic stent, so polyether polyurethane (PU) and nickel-titanium (NiTi) shape memory alloy with good biocompatibility were chosen. To minimum film thickness without degrading performance, effect of different dip coating conditions on the thickness of film were studied. To make the NiTi alloy exhibit super-elasticity at body temperature (37 C), influence of different heat treatment conditions on austenite transformation temperature (Af) and mechanical properties were studied. The results show that the customized stent grafts could meet the demand of personalized therapy, and have good performance in blasting pressure and radial support force, laying the foundation for further animal experiment and clinical experiment.

[发布机构] Department of Mechanical Engineering, Biomanufacturing Center, Tsinghua University, Beijing; 100084, China^1;Biomanufacturing and Rapid Forming Technology, Key Laboratory of Beijing, Beijing; 100084, China^2;Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, Beijing; 100084, China^3

[效力级别] 航空航天工程 [学科分类] 航空航天科学

[关键词] Animal experiments;Aortic dissections;Austenite transformations;Blasting pressure;Clinical experiments;Heat treatment conditions;Personalized therapies;Thickness of films