Cardiac Cryoablation Catheter

心脏冷冻消融导管

• 批准号: 7481457
• 负责人: Jeffrey E Olgin
• 金额: $ 15万
• 依托单位: ADVANCED REFRIGERATION TECHNOLOGIES, INC
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7481457
• 关键词: Ablation; Address; Admission activity; Air; American; Architecture; Arrhythmia; Atmospheric Pressure; Atrial Fibrillation; Books; Breathing; Cardiac; Cardiac Surgery procedures; Cardiology; Catheterization; Catheters; Chloride Ion; Chlorides; Complex; Cryosurgery; Devices; Drops; Electronic Publishing; Endocardium; Europe; Evaluation; FDA approved; Family suidae; Fever; Freezing; Funding; Furuncles; Gases; General Population; Goals; Gold; Heart; Heart Atrium; Hospitals; Implant; Laboratories; Lasers; Left; Lesion; Life; Liquid substance; Mainstreaming; Maps; Measures; Methods; Morphology; Nitrous Oxide; Pain; Participant; Patients; Perforation; Performance; Phase; Physical condensation; Procedures; Public Health; Publishing; Pulmonary veins; Radiofrequency Catheter Ablation; Radiofrequency Interstitial Ablation; Recovery; Refrigeration; Reporting; Research; Risk; Safety; Schedule; Seminal; Staining method; Stains; Stroke; System; Techniques; Technology; Temperature; Testing; Three-Dimensional Imaging; Time; Tissues; United States National Institutes of Health; Update; Ventricular; Width; Work; clinical practice; comparative efficacy; cost; cryogenics; evaporation; exhaust; follow-up; heart rhythm; heat exchanger; in vivo; innovative technologies; lifetime risk; pressure; public health relevance; radiofrequency; success; symposium; tool; triphenyltetrazolium; valve replacement; vapor

DESCRIPTION (provided by applicant): Atrial fibrillation (AF) is the most frequent arrhythmia encountered in clinical practice and is the most common arrhythmia necessitating hospital admission. Nearly three million people in the U.S. have Atrial Fibrillation. Americans over 40 have a one in four lifetime risk of developing Atrial Fibrillation. Currently there is only one practical treatment, pulmonary vein isolation (PVI) with a radiofrequency (RF) ablation catheter. Of the 3 million people suffering from Atrial Fibrillation, only about 3,000 (0.1%) annually are treated and cured with this complex and risky procedure. RF ablation creates hyperthermia lesions and inevitably involves some degree of tissue disruption that increases the risk for perforation and stroke. In contrast, the destruction of tissue by freezing results in minimal tissue disruption and preserves basic underlying tissue architecture. Treatment using cryoablation is attractive because of its inherent safety, however the promise of cryoablation via catheterization has not yet been fully realized because of technical shortcomings. Currently used cardiac cryoablation catheters suffer from lack of cooling power. The bottleneck is in the amount of vapor that can be exhausted through the narrow catheter (like breathing through a straw). As a result, the success of cryoablation is reduced and, by necessity, radio frequency ablation has remained the treatment of choice despite its shortcomings. We propose a method to dramatically increase the cooling power of cardiac cryoablation catheters by eliminating the need to exhaust the vapor. Instead, the vapor will be re-circulated in a closed cycle miniature cryo refrigeration system. Our goal is to compress, condense and re-use the vapor inside the catheter. Advanced Refrigeration Technologies (ART) proposes to achieve these aims with two innovative technologies: 1) ART's laser-powered compressor technology and 2) ART's microchannel heat exchanger technology. The resulting liquefier (compressor+condenser) will eliminate the need to exhaust the vapor all together. During Phase I the following three specific aims will be addressed: 1. Feasibility of our laser-powered compressor technology to pressurize vapor to liquefaction pressure. 2. Feasibility of our heat exchanger technology to effectively cool, condensate and liquefy the vapor. 3. Demonstration of cryoablation on live heart tissue. In subsequent work, the device will be implanted in a cardiac cryoablation balloon catheter. Stronger cryo will impact public health by providing to the mainstream electrocardiologists a safe tool to treat the general public. PUBLIC HEALTH RELEVANCE: Three million people in the U.S. suffer from Atrial Fibrillation. Americans over 40 years old have a one in four risk of developing Atrial Fibrillation in their lifetime. Currently, only 3,000 (0.1%) annually are treated with a procedure that is complex, risky and not widely available. This project will help develop a device that will provide doctors a safer, simpler and lower cost procedure that will serve larger numbers of people suffering from this debilitating condition.

描述（由申请人提供）：房颤（AF）是临床实践中最常见的心律失常，也是最常见的需要住院的心律失常。在美国有近300万人患有心房颤动。40岁以上的美国人一生中患心房颤动的风险为四分之一。目前只有一种实用的治疗方法，即使用射频（RF）消融导管进行肺静脉隔离（PVI）。在300万房颤患者中，每年只有约3,000人（0.1%）通过这种复杂而危险的手术治疗和治愈。射频消融会造成高温损伤，不可避免地会造成一定程度的组织破坏，从而增加穿孔和中风的风险。相比之下，冷冻对组织的破坏导致最小的组织破坏并保留基本的底层组织结构。使用冷冻消融的治疗是有吸引力的，因为其固有的安全性，但是，通过导管冷冻消融的承诺尚未完全实现，因为技术上的缺陷。目前使用的心脏冷冻消融导管缺乏冷却能力。瓶颈在于可以通过狭窄的导管排出的蒸汽量（就像通过吸管呼吸一样）。因此，冷冻消融术的成功率降低，并且出于必要，射频消融术尽管存在缺点，但仍然是治疗的选择。我们提出了一种方法，以显着增加冷却功率的心脏冷冻消融导管，消除了需要排气的蒸汽。相反，蒸汽将在封闭循环微型低温制冷系统中再循环。我们的目标是压缩，冷凝和重复使用导管内的蒸汽。先进制冷技术（ART）提出通过两项创新技术实现这些目标：1）ART的激光驱动压缩机技术和2）ART的微通道热交换器技术。由此产生的净化器（压缩机+冷凝器）将消除对一起排出蒸汽的需要。在第一阶段，将实现以下三个具体目标：1.我们的激光驱动压缩机技术将蒸汽加压至液化压力的可行性。2.我们的热交换器技术的可行性，以有效地冷却，冷凝和蒸发蒸汽。3.冷冻消融术在活体心脏组织上的演示。在后续工作中，该器械将植入心脏冷冻消融球囊导管中。更强的冷冻将通过为主流心电图专家提供治疗普通公众的安全工具来影响公共卫生。公共卫生相关性：美国有300万人患有房颤。40岁以上的美国人一生中有四分之一的风险发生房颤。目前，每年只有3,000人（0.1%）接受复杂、危险且不广泛使用的手术治疗。该项目将帮助开发一种设备，为医生提供更安全，更简单，成本更低的程序，为更多患有这种衰弱疾病的人提供服务。