THROMBORESISTANT POLYURETHANE CARDIAC VALVE DEVELOPMENT

一种新型聚氨酯人工心脏瓣膜的研制 材料已经制造并在体外测试。 这些 初步测试表明，该装置是耐用的（无故障 在持续至少2亿次循环的测试中）， 血流动力学特征与目前可用的相似 阀门. 为这种用途开发的分段聚脲是独一无二的 因为它的体积特性，长期耐用性，和表面 生物相容性特性已被分离， 由两种不同的材料制成。 两者的融合 组分导致单一材料结合了 每个人的属性。 该材料棒的体内评价， 的心室辅助装置泵囊已经证明了其 优异的物理和抗血栓特性。 我们建议制造瓣膜，并在体外和体内进行测试。 vivo. 稳态和脉动条件将用于 模拟回路测试。 将在左心室植入瓣膜， 小牛的主动脉分流，我们已经多次使用这个模型来 评估其他设备。 将进行额外的血流动力学测试， 对植入瓣膜进行SEM和X射线分析。

A new cardiac valve fabricated from a novel polyurethane material has been fabricated and tested in vitro. These preliminary tests indicate that this device is durable (no failures in tests lasting at least 200 million cycles) and possesses hemodynamic characteristics comparable to currently available valves. The segmented polyurethaneurea developed for this use is unique because its bulk properties, for long-term durability, and surface properties, for biocompatibility, have been separated and developed in two distinct materials. Blending of the two components results in a single material incorporating the properties of each. In vivo evaluation of rods of this material and of ventricular assist device pumping sacs has demonstrated its excellent physical and thromboresistant characteristics. We propose to fabricate valves and test them both in vitro and in vivo. Steady-state and pulsatile conditions will be used for the mock loop testing. Valves will be implanted in left ventricle to aorta shunts in calves, a model that we have used many times to evaluate other devices. Additional hemodynamic testing will be performed on explanted valves, as will SEM and X-ray analysis.