New generation of catheters for treatment of atrial fibrillation

描述（由申请人提供）：房颤仍然是最常见的心律失常。它与较低的生活质量和较高的发病率和死亡率有关。以消除房颤为目的的冷冻疗法和射频导管消融已成为主流治疗选择。它们产生的病变阻止了电活动从异常活动部位（包括肺静脉）的传播。如今，在心脏消融手术期间，用于实时监测组织损伤的手段有限。为了满足这一需求，我们研究了内源性NADH的荧光作为消融过程中组织损伤的活体标记，并证实了这种方法在血液灌注动物心脏中的可行性。STTR第一阶段的支持将为我们提供必要的资金，以加快项目进入下一阶段。研究将在小型和大型、完全麻醉开胸动物中进行。目标1旨在比较基于激光与LED的照明的有效性、内部与外部摄像机的灵敏度和空间分辨率，并测试可充盈球囊的形状和材料，以及将所有组件安装在12 Fr（4 mm）直径导管的管腔内。在Aim 2中，LuxCath设计的导管的几个迭代将被带到GWU外科内窥镜研究所（WISE）手术室进行测试。将在真实的时间内采集NADH荧光图像，以可视化各种临床相关部位（包括肺静脉）消融病变之间的存活组织间隙。电活动记录将与NADH图像相关联，以将消融间隙与消融后折返的发生相关联。第一阶段的直接目标是开发一种临床前独立可视化导管，可在房颤消融术期间使用，以评价肺静脉口周围的心脏病变。最终，将开发新一代独立可视化导管以及具有可视化功能的消融导管，从而实现实时可视化。 在消融时使用消融的组织或使用相同的器械进行消融。这些新的成像技术将为更简单、更快、更安全、更具成本效益和更可靠的微创AF消融手术铺平道路。

DESCRIPTION (provided by applicant): Atrial fibrillation remains the most commonly occurring cardiac arrhythmia. It is associated with a lower quality of life and a higher rate of morbidity & mortality. Cryotherapy and radiofrequency catheter ablations for the purpose of eliminating atrial fibrillation have become a mainstream treatment option. They produce lesions that block the spread of electrical activity from the sites of abnormal activity, including the pulmonary veins. Today, there are limited means for real-time monitoring of tissue injury during cardiac ablation procedures. To address this need, we studied the fluorescence of endogenous NADH as a live marker of tissue injury during the ablation procedure and have confirmed the feasibility of this approach in blood perfused animal hearts. STTR Phase I support will provide us with the necessary funds to accelerate the project into its next phase. Studies will be conducted in small and large, fully-anesthetized open-chest animals. The goals of Aim1 are to compare the effectiveness of laser vs LED based illumination, sensitivity and spatial resolution of internal vs external cameras, and to test the shape and material for the inflatable balloons and to fit all the components within lumen of a 12Fr (4mm) diameter catheter. In Aim 2 several iterations of catheters designed by LuxCath will be brought to the GWU Institute of Surgical Endoscopy (WISE) surgical suite for testing. Images of NADH fluorescence will be acquired in real time to visualize gaps of viable tissue between ablation lesions at various clinically relevan sites, including the pulmonary veins. Electrical activity recordings will be linked to NADH images to correlate ablation gaps to the occurrence of post-ablation reentries. The immediate goal of Phase I is to develop a pre-clinical stand-alone visualization catheter that can be used during AF ablation procedures to evaluate the cardiac lesions around the ostia of the pulmonary veins. Ultimately, a new generation of stand- alone visualization catheters as well as ablation catheters incorporating visualization capabilities will be developed thus enabling real-time visualization of ablated tissue at the time of ablation or using the same device to perform the ablations. Such new imaging technologies will pave the way for easier, faster, safer, more cost-effective, and more reliable minimally invasive AF ablation procedures..