Film-like Acoustic Microresonators for Wireless Monitoring of Intracardiac Pressure using Ultrasound

使用超声波无线监测心内压的薄膜式声学微谐振器

• 批准号: 10396479
• 负责人: Seyedhamidreza Alaie
• 金额: $ 18.97万
• 依托单位: NEW MEXICO STATE UNIVERSITY LAS CRUCES
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-05-01 至 2025-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10396479
• 关键词: Acoustics; Affect; American; Atrial Heart Septal Defects; Attenuated; Chronic; Communication; Congestive; Detection; Devices; Echocardiography; Electromagnetic Energy; Electromagnetics; Electronics; Engineering; Equipment Malfunction; Event; Evolution; Film; Frequencies; Future; Gases; Geometry; Healthcare Systems; Heart Atrium; Heart failure; Hospital Costs; Hospitalization; Human body; Hydrocephalus; Imaging Device; Implant; In Vitro; Intracranial Pressure; Left; Left atrial structure; Life; Liquid substance; Materials Testing; Measurement; Medical; Medical Imaging; Microbubbles; Miniaturization; Monitor; Organ; Patients; Periodicity; Physicians; Physiologic Monitoring; Physiological; Polymers; Procedures; Protocols documentation; Pulmonary artery structure; Research; Resolution; Right ventricular structure; Risk; Route; Safety; Semiconductors; Side; Signal Transduction; System; Technology; Tecoflex; Testing; Textiles; Thick; Thrombosis; Time; Tissues; Travel; Ultrasonic Transducer; Ultrasonic wave; Ultrasonics; Ventricular; Water; Wireless Technology; attenuation; base; dacron; design; flexibility; heart motion; hemocompatibility; hemodynamics; high risk; implantable device; implanted sensor; in vivo; in vivo evaluation; innovation; intracardiac pressure; medical attention; miniaturize; minimally invasive; next generation; nitinol; novel; polydimethylsiloxane; pressure; prevent; radio frequency; remote monitoring; sensor; simulation; temporal measurement; tool; transmission process; ultrasound; water vapor; wireless communication; wireless fidelity; wireless implant; wireless sensor

Abstract While wireless monitoring of intracardiac pressure using implants is essential for the management of heart failure, miniaturizing these implants is critical for reducing their associated complications. Current implants mainly consist of an electromagnetic antenna, electronics, and energy-storage and conversion units. However, these units contain toxic materials, and a large antenna is necessary to transmit the large wavelengths (>5 cm) of electromagnetic waves. The size and inorganic components of the current implants increase the risk of complications for patients. Ultrasound technology is promising to replace electromagnetic waves for in vivo wireless communications. It is safe, does not interfere with other electromagnetic signals, has lower in vivo signal attenuation, and permits the use of significantly smaller antennas and implants due to its sub-millimeter wavelength. Therefore, communication through ultrasound is ideal for use in minimally invasive pressure monitoring implants. The long- term objective is to develop an ultrasound-based, wireless technology that will miniaturize intracardiac implants by eliminating both the electromagnetic antenna and the energy storage and conversion units. The objective of this project is to utilize flexible, acoustic microresonators (100 to 500 µm thick films) with compressible microcavities for physiological pressure measurements of atriums and ventricles. Our central hypothesis is that the post-processing of echo signals from the resonators and their resonant frequencies can detect intracardiac pressure changes. Our rationale is that micro-fabricated films made from polydimethylsiloxane (PDMS) form acoustic resonators. Incorporating gas/void filled microcavities into the PDMS film creates a resonator that is sensitive to the pressure difference between the inside and outside. Changing the differential pressure causes deformations of the resonator. These deformations shift the film's resonant frequency allowing for the detection of pressure changes. Our specific aims are to 1) prove the measurement sensitivity of the resonator underwater at the ventricular and atrial physiological pressures with the resolution of ~1mmHg and temporal resolution of 40 (ms); 2) demonstrate the safety of an implantable device in vitro by incorporating hemocompatible materials, testing a device's durability, and testing in a specially designed phantom; and 3) prove that the implant is suitable for a minimally invasive delivery (transseptal procedure) on a benchtop test setup. Upon project completion, the technology can be immediately employed to create safer next-generation in vivo pressure monitoring implants that operate solely using acoustic waves. This contribution is significant because it can aid over 6 million Americans who live with Heart Failure (HF), resulting in chronic hospitalizations that cost $16 billion. The proposed research is innovative because this technology employs only acoustic waves; avoids energy conversion, storage units, and electromagnetic antennas; and significantly reduces an implant's size and complications.

抽象的 虽然无线监测对心脏的心脏压力对于管理心脏是必不可少的 失败，将这些牙齿化的小型化对于减少其相关并发症至关重要。当前的诱因主要是 由电子天线，电子设备以及能量存储和转换单元组成。但是，这些 单位包含有毒物质，并且需要一个大天线来传输大波长（> 5 cm） 电磁波。当前实施的大小和无机组件增加了 患者的并发症。 超声技术有望替换电磁波用于体内无线通信。这是 安全，不会干扰其他电子信号，体内信号衰减较低，并允许使用 由于其亚毫米级波长，使用明显较小的天线和即将。所以， 通过超声通信非常适合用于微创压力监测的直接。长期 术语目标是开发一种基于超声的无线技术，该技术将使心脏内植入术微型化 通过消除电子天线和能量存储和转换单元。目的 该项目是利用可压缩的灵活的声学微孔子（100至500 µm厚的膜） 中庭和心室的物理压力测量的微腔。 我们的中心假设是，谐振器及其共振的回声信号的后处理 频率可以检测到心脏内压的变化。我们的理由是由 聚二甲基硅氧烷（PDMS）形成声学谐振器。将气体/空隙填充的微腔纳入PDM 电影创建了一个对内部和外部之间的压力差敏感的谐振器。更改 差异导致谐振器的变形。这些变形改变了电影的共鸣 允许检测压力变化的频率。 我们的具体目的是1）证明心室下水下谐振器的测量敏感性和 〜1mmHg分辨率和40（ms）的暂时分辨率的心房生理压力； 2）演示 通过掺入血液相容的材料，测试设备的植入设备在体外的安全性 耐用性，并在专门设计的幻影中进行测试； 3）证明该植入物适合最小 台式测试设置上的侵入性交付（转换过程）。项目完成后，技术可以 立即被雇用以创建一个仅操作的体内压力监测的下一代 使用声波。这项贡献很重要，因为它可以帮助超过600万与与之相处的美国人 心力衰竭（HF），导致长期住院费用为160亿美元。拟议的研究是创新的 因为这项技术员工只有声波；避免能源转换，存储单元和 电子天线；并大大降低了植入物的大小和并发症。