Miniaturization of the low-shear pulsatile TORVAD for pediatric heart failure

用于治疗小儿心力衰竭的低剪切脉动 TORVAD 的小型化

• 批准号: 9031144
• 负责人: Jeffrey Robert Gohean
• 金额: $ 39.45万
• 依托单位: WINDMILL CARDIOVASCULAR SYSTEMS, INC.
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9031144
• 关键词: Acute; Address; Adult; Animal Experiments; Animal Model; Arrhythmia; Biological Preservation; Blood; Blood flow; Body Surface Area; Cardiac Output; Cardiovascular system; Ceramics; Characteristics; Child; Childhood; Chronic; Clinical; Complication; Computer Simulation; Coupling; Development; Devices; Ensure; Event; Goals; Health; Health Sciences; Heart; Heart failure; Heating; Hematology; Hemolysis; Hemorrhage; Homeostasis; Implant; In Vitro; Incidence; Life; Liquid substance; Magnetism; Mechanics; Methodology; Miniaturization; Modeling; Molecular Weight; Motion; Motor; Neurologic; Neurologic Dysfunctions; Operating System; Patient-Focused Outcomes; Patients; Pediatrics; Pennsylvania; Performance; Pharmaceutical Preparations; Phase; Platelet Activation; Pulsatile Flow; Pump; Speed; Stroke; Stroke Volume; Sturnus vulgaris; Surface; System; Temperature; Testing; Texas; Thrombosis; Thrombus; Tissues; Trauma; Universities; Ventricular; Work; aortic valve; biomaterial compatibility; blood pump; design; hemodynamics; implantation; in vitro testing; miniaturize; operation; pediatric heart failure; pediatric patients; pressure; research study; response; sensor; shear stress; success; ventricular assist device; von Willebrand Factor

 DESCRIPTION (provided by applicant): The goal of this project is to develop a miniaturized, pediatric version of the TORVADTM, a unique ventricular assist system that delivers low-shear, synchronous, pulsatile flow, using controlled piston motion within a toroidal chamber. Low shear is achieved by the relatively low piston speed in conjunction with localized hydrodynamic bearings that maintain bulk piston-torus gap at a fixed distance. The TORVAD synchronizes with the heart to preserve aortic valve flow and maintains autoregulation of cardiac output by the Frank-Starling mechanism. The design of the TORVAD also allows for inherent determination of differential pump pressure, without additional sensors, which can be used to manage patient's medications and flow rates. These advantages have been confirmed in preliminary studies with an adult TORVAD. In vitro tests have demonstrated that the low-shear design preserves high-molecular-weight von Willebrand factor and results in significantly reduced hemolysis as compared to a continuous flow device. In addition, hemodynamic compatibility has been demonstrated using acute and chronic animal models. The TORVAD's hematological results are unmatched by any other ventricular assist device. These preliminary findings demonstrate that the TORVAD has the potential to reduce bleeding, thrombus formation, and strokes that are associated with the use of other ventricular assist devices. The goal of this project is to develop a pediatric version of the TORVAD to be used in patients with body surface area (BSA) between 0.6 and 1.5 m2. The feasibility of a pediatric TORVAD has been demonstrated through the development and testing of the adult version, where computational models for hemodynamics, heat transfer, motor design, fluid dynamics, and magnetostatics were used to design, fabricate, and verify performance with the assembled pump. For this work we will (1) Use the established computational design methodology to miniaturize the device for pediatric patients with a BSA between 0.6 and 1.5 m2; (2) Fabricate five devices and perform design verification; (3) Conduct in vitro experiments to assess hemolysis, high-molecular-weight von Willebrand factor preservation, and platelet activation; and (4) Perform three acute animal experiments to assess implantability, hemodynamic performance, and synchronization.

 描述（由申请人提供）：该项目的目标是开发 TORVADTM 的小型化儿科版本，这是一种独特的心室辅助系统，通过在环形室内使用受控活塞运动来提供低剪切、同步、脉动流。低剪切是通过相对较低的活塞速度与局部流体动压轴承相结合来实现的，局部流体动压轴承将整体活塞-圆环间隙保持在固定距离。 TORVAD 与心脏同步，以保持主动脉瓣血流，并通过 Frank-Starling 机制维持心输出量的自动调节。 TORVAD 的设计还允许固有地确定泵压差，无需额外的传感器，可用于管理患者的药物和流速。这些优点已在成人 TORVAD 的初步研究中得到证实。体外测试表明，与连续流装置相比，低剪切设计保留了高分子量冯维勒布兰德因子，并显着减少了溶血。此外，血流动力学相容性已通过急性和慢性动物模型得到证实。 TORVAD 的血液学结果是任何其他心室辅助装置都无法比拟的。这些初步研究结果表明，TORVAD 有可能减少与使用其他心室辅助装置相关的出血、血栓形成和中风。该项目的目标是开发 TORVAD 的儿科版本，用于体表面积 (BSA) 0.6 至 1.5 m2 之间的患者。儿科 TORVAD 的可行性已通过成人版本的开发和测试得到证明，其中使用血流动力学、传热、电机设计、流体动力学和静磁学的计算模型来设计、制造和验证组装泵的性能。对于这项工作，我们将 (1) 使用已建立的计算设计方法，将用于 BSA 介于 0.6 至 1.5 m2 之间的儿科患者的设备小型化； (2)制作5个器件并进行设计验证； (3) 进行体外实验评估溶血、高分子量冯维勒布兰德因子保存和血小板活化； (4) 进行三项急性动物实验以评估可植入性、血流动力学性能和同步性。