DEVELOPMENT EVALUATION OF A SYNTHETIC TRILEAFLET VALVE

在13年的计划中，已经开发出一种合成三叶阀。 临床瓣膜样机采用针织窄缝软领 聚酯、柔性冠状支架和微织布，该微织布 高度灵活，具有类似于的刚性和各向异性 正常的主动脉叶组织。广泛的耐用性和软组织植入 研究在绵羊二尖瓣置换术前进行。入内 活体数据显示瓣膜功能不全发生在早期(24小时) 这后来被追溯到细丝几何形状的改变 应力压实。新的面料设计已经完成，第二个 样机正在生产中。将阀门插入到液压测试中 一种以正向和逆流功率损耗为特征的装置。 加速疲劳试验以以下循环速率进行 1,000-12000个/分钟。植入物研究包括皮下植入 兔的材料，动脉和静脉系统的导管植入 狗和狒狒以及幼年绵羊的瓣膜植入。

During a 13 year program, a synthetic trileaflet valve has been developed. Prototype clinical valves use a narrow soft sewing collar of knitted polyster, a flexible coronal shaped stent and a micro-woven fabric which is highly flexible and has stiffness and anisotropic properties similar to normal aortic leaflet tissue. Extensive durability and soft tissue implant studies were performed prior to mitral valve replacement in sheep. The in vivo data showed that valvular insufficiency occurred early (24 hours) which has subsequently been traced to alteration of filament geometry from stress compaction. New fabric designs have been completed and a second prototype is in production. Valves are inserted into a hydraulic testing device which characterizes forward and regurgitant power losses. Accelerated fatigue testing is performed at cyclic rates of 1000-12000/min. Implant studies consist of subcutaneous placement of materials in rabbits, conduit insertions in the arterial and venous systems of dogs and baboons and valve insertion in juvenile sheep.