Reduction of Thromboembolic Potential in Cardiac Devices Via Passive Flow Control

通过被动流量控制降低心脏装置中的血栓栓塞可能性

• 批准号: 7860585
• 负责人: AJIT P YOGANATHAN
• 金额: $ 18.57万
• 依托单位: GEORGIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2012-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7860585
• 关键词: Address; Adverse effects; Animal Testing; Area; Artificial Heart; Arts; Beds; Biological; Blood; Blood Cells; Blood coagulation; Blood flow; Bypass; Cardiac; Cardiovascular system; Characteristics; Clinical; Coagulants; Coupling; Data; Development; Devices; Effectiveness; Elements; Environment; Evolution; Extravasation; Generations; Heart Valve Prosthesis; Heart Valves; Height; Hemolysis; Hemorrhage; Image; In Vitro; Institutes; Investigation; Lead; Length; Measurement; Measures; Mechanics; Methodology; Modeling; Molds; Patients; Performance; Phase; Physiological; Platelet Activation; Positioning Attribute; Preventive; Principal Investigator; Property; Prosthesis; Pulsatile Flow; Pump; Relative (related person); Research; Resolution; Risk; Shapes; Simulate; Stents; Stream; Stress; Surface; System; Technology; Testing; Thrombus; Time; Velocimetries; Work; base; clinically relevant; design; flexibility; hemodynamics; in vitro Model; in vitro testing; meetings; nano; new technology; novel; operation; particle; pressure; programs; public health relevance; response; shear stress

DESCRIPTION (provided by applicant): Blood damage caused by flow shear can cause thromboembolic complications that seriously limit the performance of a broad range of cardiovascular hardware including prosthetic valves, bypass pumps, and assist device. An attractive way to mitigate the adverse effects of high shear stress in cardiovascular hardware is to use miniature, surface-integrated passive flow control elements (e.g., vortex generators, riblets, dimples, etc.) which have already been exploited in mechanical and aerospace applications. The focus of this R21 proposal is to explore the effectiveness of relatively simple, integrable passive flow control elements to achieve significant control of blood flow within cardiovascular systems with the objective of minimizing blood damage and flow losses by controlling the evolution of coherent large-scale shear-inducing eddies in order to increase dissipation of high Reynolds stresses, or suppression and reduction of flow separation. We propose to demonstrated the feasibility of this approach in an idealized bileaflet mechanical valve test-bed where passive flow control will be implemented using miniature vortex generators in order to alleviate the instantaneous shear stresses of the pulsatile flow in between the leaflets and thereby significantly reduce shear-induced blood damage. Our preliminary work in this effort has already demonstrated reduction in turbulent stresses and diminution of blood coagulation in a steady flow model. In this study, we will build on these preliminary findings by optimizing various passive flow control configurations (including conformable protrusions) on an idealized valve test-bed and validate the effectiveness of the optimized configurations in an in vitro pulsatile blood loop. We anticipate that this research will provide the basis for a later submission of an R01 proposal aimed at a fundamental investigation, modeling, and controlling platelet activation/blood damage/thrombus formation for managing blood flow in cardiovascular hardware thus paving the way towards the realization of new design paradigm for cardiovascular hardware in which blood flow losses and damage are mitigated and controlled by novel, integrated passive flow elements. PUBLIC HEALTH RELEVANCE: Blood damage caused by flow shear causes thromboembolic complications in prosthetic heart valves. We investigate a new technology to reduce shear concentrations in blood flows and thus enable the development of a new generation of cardiovascular devices.

描述（由申请人提供）：血流剪切引起的血液损伤可导致血栓栓塞并发症，严重限制各种心血管硬件的性能，包括假体瓣膜、旁路泵和辅助装置。减轻心血管硬件中高剪切应力的不利影响的一种有吸引力的方法是使用微型，表面集成的被动流动控制元件（例如，涡流发生器，波纹，凹陷等），这些元件已经在机械和航空航天应用中得到了利用。本R21提案的重点是探索相对简单，可积分的被动流动控制元件的有效性，以实现心血管系统内的血液流动的显著控制，目的是通过控制连贯的大规模剪切诱导涡流的演变，以增加高雷诺应力的耗散，或抑制和减少流动分离，从而最大限度地减少血液损伤和流动损失。我们建议在理想的双叶机械阀试验台中证明这种方法的可行性，该试验台将使用微型涡流发生器实现被动流量控制，以减轻叶片之间脉动流的瞬时剪切应力，从而显着减少剪切引起的血液损伤。我们在这项工作中的初步工作已经证明了在稳定流动模型中湍流应力的减少和血液凝固的减少。在本研究中，我们将在这些初步研究结果的基础上，在一个理想的阀门试验台上优化各种被动流量控制配置（包括符合要求的突出部分），并验证优化配置在体外脉动血环中的有效性。我们预计这项研究将为随后提交的R01提案提供基础，该提案旨在对心血管硬件中的血流管理进行基础研究、建模和控制血小板激活/血液损伤/血栓形成，从而为实现心血管硬件的新设计范式铺平道路，在这种设计范式中，血流损失和损伤由新颖的、集成的被动血流元件减轻和控制。公共卫生相关性：血流剪切引起的血液损伤导致人工心脏瓣膜血栓栓塞并发症。我们研究了一种新的技术来降低血流中的剪切浓度，从而使新一代心血管装置的发展成为可能。

项目成果

Design of a pulsatile flow facility to evaluate thrombogenic potential of implantable cardiac devices.

设计脉动流设施以评估植入式心脏装置的血栓形成潜力。

• DOI: 10.1115/1.4029579
• 发表时间: 2015
• 期刊: Journal of biomechanical engineering
• 作者: Arjunon,Sivakkumar;Ardana,PabloHidalgo;Saikrishnan,Neelakantan;Madhani,Shalv;Foster,Brent;Glezer,Ari;Yoganathan,AjitP
• 通讯作者: Yoganathan,AjitP