Acoustically Active Catheter for Echocardiographic Navigation

描述（由申请人提供）：正在开发使用基因和细胞因子的再生疗法，用于恢复梗塞心肌沿着的功能，以及许多其他微创心脏和非心脏研究和治疗干预，使用可控导管作为风险、昂贵和要求苛刻的手术的替代方案。可操控导管导航的实时、非透视、便携式和经济高效的解决方案代表了微创介入引导的常见和关键需求。荧光镜检查、磁共振标测或磁共振成像满足这些要求的能力有限，涉及暴露于辐射，并且需要专业团队和专用房间。我们提出了一种满足所有这些要求的方法，并将在心内导航的特定领域进行测试，尽管其预期用途是广泛的。我们利用我们的创新工作原型类型的声学有源导管（AAC）：可操纵导管的尖端配备有压电晶体，该压电晶体以规定的频率振动，并作为超声扫描平面中可检测的"信标"。这样，AAC的尖端可以被沿着超声扫描平面朝向测试解剖目标引导。目的1：表征、优化并初步测试声学导管的操作模式。接收，干扰，和传输操作模式的晶体振动的AAC尖端的建议，并将explored，使尖端最佳和明确地检测超声导航扫描平面。目标2：测试AAC导航系统的精度、准确度和实用性。通过四维超声心动图实时生成的双平面经胸多普勒扫描平面将作为导航路径的新概念进行测试，用于将AAC头端转向心脏内的测试解剖目标。所提出的方法通过引入创新的声学有源导管以及与4D回波成像和导航相结合的集成超声图像引导导航系统来打破目前的现状，以进行微创干预。公共卫生相关性：在西方世界，与心脏病相关的心力衰竭仍然是发病率和死亡率的主要原因。通过使用微创干预将基因或干细胞直接输送到心肌中可以恢复其功能。微创介入也正在开发用于许多其他心脏和非心脏研究和治疗应用，并且基于仅通过使用包括可操纵导管的特殊工具的最小皮肤和血管穿刺进入靶器官。通过这种方式，可以避免风险，昂贵和苛刻的手术。微创介入的共同需求是导航到解剖目标。然而，不需要暴露于X射线、昂贵的成像设备或专门的房间，并且还精确地导航微创介入工具（诸如可操纵的心内导管）的系统并不存在。我们建议探索一种利用我们创新的声有源导管的解决方案。这种导管的远端产生独特的声学信号，该信号在超声图像中被检测为"bea-con"。通过用超声描绘心脏和特定解剖目标，可以通过非常相同的技术来导航新型导管。因此，相对便宜的、便携式的和广泛可用的超声检查具有作为成像和导航工具的作用。该拨款申请旨在初步验证所提出的超声图像引导导航系统的可行性，精度和准确性。

DESCRIPTION (provided by applicant): Regenerative therapies with genes and cellular agents are being developed for restoration of function in in-farcted myocardium along with many other minimally invasive cardiac and noncardiac investigative and therapeutic interventions with steerable catheters as alternatives to risky, costly, and demanding surgery. A real-time, nonfluoroscopic, portable, and cost-effective solution for steerable catheter navigation repre- sents a common and critical need for guidance of the miniminally invasive interventions. Fluoroscopy, elec- tromechanical mapping, or magnetic resonance imaging have limited ability to fulfill these requirements, in- volve exposure to radiation, and require a specialized team and a dedicated room. We propose an approach that satisfies all these requirements and is to be tested in a specific field of in- tracardiac navigation, although its anticipated utility is broad. We capitalize on our innovative working proto- type of an Acoustically Active Catheter (AAC): A tip of a steerable catheter is outfitted with a piezoelectric crystal that vibrates at a prescribed frequency and acts as a "beacon" detectable in ultrasound scan planes. As such, the tip of the AAC can be guided along ultrasound scan planes toward a testing anatomic target. Aim 1: Characterize, optimize, and initially test operating modes of the acoustic catheter. Receive, interfer- ence, and transmission operating modes of the crystal vibrating at the AAC tip are proposed and will be ex- plored to make the tip optimally and unambiguously detectable in ultrasound navigation scan planes. Aim 2: Test the precision, accuracy, and utility of the AAC navigation system. Biplane transthoracic Doppler scan planes, generated in real-time by 4-dimensional echocardiography, will be tested as a novel concept of navigation pathways for steering the AAC tip towards a testing anatomic target within the heart. The proposed approach disrupts the current status quo by introducing an innovative acoustically active catheter and, in conjunction with 4D echo imaging and navigation, an integrated ultrasound image-guided navigation system for minimally invasive interventions. PUBLIC HEALTH RELEVANCE: Infarction-related heart failure remains a major cause of morbidity and mortality in the Western world. Deliv- ery of genes or stem cells directly into the cardiac muscle by using minimally invasive interventions can re- store its function. The minimally invasive interventions are being developed also for many other cardiac and noncardiac investigative and therapeutic applications, and are based on accessing a target organ only through a minimal skin and vascular puncture with special tools including steerable catheters. In this way, a risky, costly, and demanding surgery can be avoided. The common need of the minimally invasive interventions is navigation to an anatomic target. However, a system that does not require exposure to X-rays, expensive imaging devices, or a specialized room - and yet, accurately navigates the minimally invasive intervention tool, such as a steerable intracardiac catheter - does not exist. We propose to explore a solution that capitalizes on our innovative Acoustically Active Catheter. The distal end of such a catheter produces a unique acoustic signal that is detected in ultrasound images as a "bea- con". By depicting the heart and the specific anatomic target with ultrasound, the novel catheter can be navigated by the very same technique. Thus, the relatively inexpensive, portable, and broadly available ul- trasonography has a role as both an imaging and navigation tool. This grant application is designed to initially validate the feasibility, precision, and accuracy of the proposed ultrasound image-guided navigation system.