Physiological Adaptive COntrol of Continuous Flow Ventricular Assist Devices

连续流心室辅助装置的生理自适应控制

• 批准号: 8444959
• 负责人: Joshua P Cysyk
• 金额: $ 19.13万
• 依托单位: PENNSYLVANIA STATE UNIV HERSHEY MED CTR
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-02-01 至 2015-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8444959
• 关键词: Acute; Adverse event; Algorithms; Animal Testing; Artificial Organs; Blood; Blood flow; Cause of Death; Cessation of life; Chronic; Custom; Destinations; Detection; Device Designs; Device or Instrument Development; Devices; Event; Exercise; FDA approved; Feedback; Frequencies; Generations; Head; Heart; Heart Diseases; Heart failure; Hospitals; In Vitro; Left; Measurement; Measures; Myocardial; Operating System; Patients; Physiological; Pump; Research; Risk; Safety; Series; Sheep; Signal Transduction; Speed; Staging; Sturnus vulgaris; Suction; System; Testing; Therapeutic; Time; Transplantation; United States; Ventricular; Ventricular Arrhythmia; active control; base; blood pump; experience; hemodynamics; improved; pressure; prevent; public health relevance; response; sensor; ventricular assist device

DESCRIPTION (provided by applicant): The use of left ventricular assist devices (LVADs) has been a viable therapeutic option for end-stage heart failure patients. These devices are commonly used as bridge-to-transplant or destination therapy, and as the risk of adverse events has been reduced with improved device design, LVAD support is being considered as an option for class III heart failure patients as well. Recently, the use of continuous flow LVADs has become common due to their small size and improved reliability. However, control of these devices can be challenging as opposed to the previous generation of pulsatile devices. Current control systems operate the pump at a fixed speed set by the clinician. The speed is set high enough to provide adequate circulatory support but not too high as to cause suction and ventricular collapse. These control systems cannot increase flow in response to physiologic demand and therefore, patients with these devices have limited exercise capacity. As patients are now leaving the hospital and returning to their daily activities, a control system that respond to patient demand is necessary. The primary objective of the proposed research is to develop a control system for continuous flow blood pumps that can reduce the risk of suction and adapt pump flow in response to circulatory demand. We have developed a pressure sensor that can be integrated to the inlet of a continuous flow LVAD and maintain a seamless blood interface. Using this pressure sensor, the following specific aims of the control system will be developed. (1) The onset of ventricular suction can be detected as a negative transient in the inlet pressure signal, and pump speed can be immediately reduced to resolve the suction event. (2) The peak-to-peak inlet pressure signal can be used in a feedback control loop to mimic the Frank-Starling mechanism and maintain adequate circulatory support in response to changes in ventricular preload. (3) The control system set point can be automatically adjusted based on the frequency of detected suction events in order to adapt to physiologic changes. The control system has been developed in vitro using the FDA approved HeartMate II axial flow pump, and tested in an initial acute sheep study. We propose to further develop and evaluate the control system in a series of acute and chronic sheep studies. The Penn State Division of Artificial Organs has extensive experience and expertise in LVAD development and large animal testing that we will utilize for the proposed research.

描述（由申请人提供）：左心室辅助装置（LVAD）的使用是终末期心力衰竭患者的一种可行治疗选择。这些器械通常用作移植桥或目的地治疗，由于器械设计的改进降低了不良事件的风险，LVAD支持也被视为III类心力衰竭患者的一种选择。近来，连续流LVAD的使用由于其小尺寸和改进的可靠性而变得普遍。然而，与上一代脉动装置相反，这些装置的控制可能具有挑战性。当前的控制系统以由临床医生设定的固定速度操作泵。速度设置得足够高，以提供足够的循环支持，但不能太高，以免引起抽吸和心室塌陷。这些控制系统不能根据生理需求增加流量，因此，使用这些器械的患者的运动能力有限。由于患者现在离开医院并恢复日常活动，因此需要响应患者需求的控制系统。拟议研究的主要目标是开发一种用于连续流血泵的控制系统，该系统可以降低抽吸风险并根据循环需求调整泵流量。我们已经开发出一种压力传感器，可以集成到连续流LVAD的入口，并保持无缝的血液接口。使用该压力传感器，将开发控制系统的以下特定目标。(1)心室抽吸的开始可以被检测为入口压力信号中的负瞬态，并且可以立即降低泵速以解决抽吸事件。(2)峰-峰入口压力信号可用于反馈控制回路，以模拟Frank-Starling机制，并响应心室前负荷的变化维持足够的循环支持。(3)控制系统设定点可以基于检测到的抽吸事件的频率来自动调整，以便适应生理变化。该控制系统是使用FDA批准的HeartMate II轴流泵在体外开发的，并在最初的急性绵羊研究中进行了测试。我们建议在一系列急性和慢性绵羊研究中进一步开发和评估控制系统。宾夕法尼亚州立大学人工器官部门在LVAD开发和大型动物试验方面拥有丰富的经验和专业知识，我们将利用这些经验和专业知识进行拟议的研究。