Acoustically Active Catheter for Echocardiographic Navigation

描述（由申请人提供）：利用基因和细胞药物的再生疗法正在被开发，用于恢复梗死心肌的功能，以及许多其他微创心脏和非心脏调查和治疗干预，使用可操纵导管作为风险，昂贵和要求高的手术的替代方法。一种实时、非透视、便携、成本效益高的可操纵导尿管导航解决方案代表了对微创干预指导的共同和关键需求。透视、机电测绘或磁共振成像在满足这些要求方面的能力有限，涉及辐射暴露，需要专门的团队和专门的房间。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，尽管其预期的用途是广泛的。我们利用我们的声学主动导管（AAC）的创新工作原型：可操纵导管的尖端配备了一个压电晶体，该晶体以规定的频率振动，并作为超声扫描平面可检测的“信标”。因此，AAC的尖端可以沿着超声扫描平面引导到测试解剖目标。目的1：表征、优化和初步测试声导管的操作模式。提出了晶体振动在AAC尖端处的接收、干扰和传输工作模式，并将对其进行探索，以使尖端在超声导航扫描平面上得到最佳和明确的检测。目标2：测试AAC导航系统的精度、准确性和实用性。由四维超声心动图实时生成的双翼经胸多普勒扫描平面将作为一种新的导航路径概念进行测试，用于将AAC尖端转向心脏内的测试解剖目标。提出的方法通过引入一种创新的声主动导管，并结合4D回声成像和导航，一种用于微创干预的集成超声图像引导导航系统，打破了目前的现状。公共卫生相关性：梗死相关性心力衰竭仍然是西方世界发病率和死亡率的主要原因。通过微创干预将基因或干细胞直接注入心肌可以恢复心肌的功能。微创干预也正在开发用于许多其他心脏和非心脏的调查和治疗应用，并且基于仅通过最小的皮肤和血管穿刺，使用包括可操纵导管在内的特殊工具进入目标器官。这样，就可以避免高风险、高成本和高要求的手术。微创介入的共同需求是导航到解剖目标。然而，不需要暴露在x射线下，不需要昂贵的成像设备，也不需要专门的房间，但却能准确地导航微创干预工具，如可操纵的心内导管，目前还不存在。我们建议探索一种利用我们创新的声主动导管的解决方案。这种导管的远端产生一种独特的声信号，在超声图像中被检测到为“bea- con”。通过用超声波描绘心脏和特定的解剖目标，这种新型导管可以用同样的技术进行导航。因此，相对便宜、便携和广泛使用的超音波成像具有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.