Ultrasound-Guided Delivery System for Accurate Positioning/Repositioning of Transcatheter Aortic Valves

项目总结 拟议的项目旨在开发和测试一种用于植入的新型超声引导输送系统 经导管主动脉瓣。这项新技术将使准确定位和重新定位 在植入过程中确保瓣膜功能，避免瓣膜旁渗漏和冠脉狭窄 障碍物。 目前，实时透视成像不足以准确地确定 大动脉解剖。植入不当可能会导致植入的瓣膜阻塞冠状静脉口，或者 高度钙化瓣膜中的碎片错位。经食道超声心动图(TEE)研究 作为TAVR程序的一种补充成像方式；然而，TEE的操作分辨率较低，可以 会导致严重的并发症，对大多数患者来说是不舒服的。此外，T形三通要求通用 在手术过程中麻醉，并推动仅在清醒镇静下进行TAVR， 这将不允许在长时间内使用TEE。该项目旨在结合血管内 超声(IVUS)已成功地用于冠状动脉支架的最佳定位，与我们的 用于TAVR手术的可重新定位/可回收的输液导管。我们假设IVUS将协助 准确成像主动脉环和根部，从而改进TAVR植入程序 与传统的TEE引导手术相比。我们将在此范围内实现以下具体目标 奖项为期两年： 具体目标1：设计和构建一种集成的超声引导传递系统，以实现 经导管主动脉瓣的定位/再定位。 具体目标2：论证IVUS引导下瓣膜置入术的临床可行性 在绵羊模型中(在先前植入的钙化聚合主动脉瓣内)并测试其功能。 然后将该手术的结果变量与常用的TEE引导植入进行比较 程序。

PROJECT SUMMARY The proposed project aims to develop and test a novel ultrasound-guided delivery system for implanting transcatheter aortic valves. This new technology will enable accurate positioning and repositioning of the device during implantation to ensure valvular competency, and avoid paravalvular leakage and coronary ostia obstruction. Currently, real-time fluoroscopy imaging is insufficient to accurately identify optimal deployment areas in the aortic anatomy. Improper implantation may result in obstruction of coronary ostia by the implanted valve, or debris dislocation in a highly calcified valve. Transesophageal Echocardiography (TEE) has been investigated as a complementary imaging modality for TAVR procedures; however, TEE operates at a lower resolution, can result in significant complications, and is uncomfortable for most patients. Additionally, TEE requires general anesthesia during the procedure, and a push is being made to perform TAVR solely under conscious sedation, which would not allow the use of TEE over long time periods. This project aims to combine intravascular ultrasound (IVUS), which has been used successfully to optimally position coronary artery stents, with our repositioning/retrievable delivery catheter for TAVR procedure. We hypothesize that IVUS will assist in accurate imaging of the aortic annulus and root, allowing for an improved TAVR implantation procedure compared to conventional TEE-guided procedures. We will accomplish the following specific aims within this award's two-year duration: Specific Aim 1: Design and construct an integrated ultrasound-guided delivery system for accurate positioning/repositioning of transcatheter aortic valves. Specific Aim 2: Demonstrate the clinical feasibility of IVUS-guided valve implantation by delivering the valves in a sheep model (within a previously-implanted calcified polymeric aortic valve) and testing its functionality. Then compare the procedure's outcome variables to commonly-practiced TEE-guided implantation procedures.