Resistance to Aortic Endograft Migration: Comparative Effectiveness of FDA Approv

描述（由申请人提供）： 本申请涉及广泛的挑战领域（05）比较有效性研究（CER）和特定的挑战主题05-EB-105：医疗植入物的比较有效性。腹主动脉瘤（AAA）的患病率在美国人群中显著增加，影响5%-7%的60岁以上的美国人。在过去的十年中，动脉瘤腔内修复术已成为动脉瘤疾病的主要治疗方法。目前，有5种经FDA批准的腹主动脉瘤覆膜支架：Medtronic AneuRx、戈尔Excluder、Cook Zenith、Endologix Excluder和Medtronic Talent。这些器械中的每一种都具有不同的设计和固定机制。血管内修复是一种微创手术，与开放性修复相比，可降低围手术期发病率和死亡率。然而，血管内手术由于失去长期位置稳定性（即，迁移）。覆膜支架失效导致昂贵的二次手术、转为开放修复、长期监测和死亡。了解覆膜支架在体内经历的生物力学环境是确保器械正确发挥功能和长期耐用性的关键因素。这项工作的目标有两个：首先，我们将开发和应用一套工具来表征覆膜支架的体内力学行为，总体目标是确定覆膜支架迁移的可能性。其次，我们将对5种AAA覆膜支架的移位进行有效性比较研究。我们将使用3D分割技术生成植入覆膜支架的AAA患者特定计算机模型。然后，我们将进行计算流体动力学（CFD）分析，以评价作用在器械上的血流动力学力。CFD分析将依赖于边界条件规范的复杂方法，以获得覆膜支架计算机模型中的真实流量和压力分布。然后，我们将进行计算固体力学（CSM）分析，以评价覆膜支架在与血管壁的附着区产生的固定力。使用每种覆膜支架治疗的患者的系列随访成像纵向研究将提供必要的统计数据，以获得计算研究的移位可能性。我们组建的研究团队由领先的生物工程师、机械工程师、放射科医生和临床医生组成，将由Christopher K.斯坦福大学的Zarins是AAA疾病血管内治疗的开发和临床应用方面的领先研究员。Zarins博士一直大力倡导使用成像和模拟工具来改进医疗器械设计，开发更安全、更有效的医疗产品。本研究将是首次尝试使用同类最佳成像、CFD和计算固体力学工具组合表征AAA覆膜支架迁移问题。此外，这项工作将提供5种当前FDA批准的AAA覆膜支架的首次有效性比较研究。主动脉覆膜支架迁移阻力：FDA批准器械的比较有效性。 公共卫生相关性： 腔内修复术已成为腹主动脉瘤（AAA）疾病的主要治疗方法。目前有5种FDA批准的覆膜支架器械用于AAA修复。对这些器械所经历的真实体内生物力学环境知之甚少。此外，目前没有研究比较不同器械在长期位置稳定性（移位）方面的性能。

DESCRIPTION (provided by applicant): This application addresses broad Challenge Area (05) Comparative Effectiveness Research (CER) and specific Challenge Topic 05-EB-105: Comparative Effectiveness of Medical Implants. The prevalence of abdominal aortic aneurysms (AAA) has increased significantly in the American population, affecting 5-7% of Americans over age 60. During the past decade endovascular aneurysm repair has become the primary treatment for aneurysm disease. Currently, there are 5 FDA approved abdominal aortic aneurysm endografts: Medtronic AneuRx, Gore Excluder, Cook Zenith, Endologix Powerlink, and Medtronic Talent. Each of these devices presents different designs and fixation mechanisms. Endovascular repair is a minimally invasively procedure that reduces perioperative morbidity and mortality when compared to open repairs. However, endovascular procedures are prone to late failure due to the loss of long-term positional stability (i.e., migration) of the endograft as a result of the pulsatile forces of blood flow. Endograft failure results in costly secondary procedures, conversion to open repair, long-term surveillance, and death. Understanding the biomechanical environment experienced by endografts in vivo is a critical factor to ensure correct functioning and long term durability of the device. The goal of this work is two-fold: First, we will develop and apply a set of tools to characterize the mechanical behavior of endografts in vivo with the overall goal of determining the likelihood of migration of the endograft. Second, we will perform a comparative effectiveness study with regards to migration of the 5 AAA endografts. We will use 3D segmentation techniques to generate patient- specific computer models of AAAs with implanted endografts. Then, we will perform Computational Fluid Dynamics (CFD) analyses to evaluate the hemodynamic forces acting on the device. The CFD analysis will rely on sophisticated methods for boundary condition specification to obtain realistic distributions of flow and pressure in the computer model of the endograft. We will then perform a Computational Solid Mechanics (CSM) analysis to evaluate the fixation forces developed by the endograft in the attachment zones with the vessel wall. Longitudinal studies of serial follow-up imaging of patients treated with each endograft will provide the necessary statistical data to obtain a likelihood of migration for the computational studies. The research team we have assembled consists of leading bioengineers, mechanical engineers, radiologists, and clinicians and will be led by Dr Christopher K. Zarins at Stanford, a leading researcher in the development and clinical application of endovascular treatments for AAA disease. Dr. Zarins has been a strong advocate for using imaging and simulation tools to improve medical device design and develop safer and more effective medical products. This research will be the first attempt to characterize the problem of migration of AAA endografts using a combination of best-in-class imaging, CFD and Computational Solid Mechanics tools. Furthermore, this work will provide the first comparative effectiveness study of the 5 current FDA approved AAA endografts. Resistance to aortic endograft migration: comparative effectiveness of FDA approved devices. Public Health Relevance: Endovascular repair has become the primary treatment for abdominal aortic aneurysm (AAA) disease. There are currently 5 FDA approved endograft devices for AAA repair. The true in-vivo biomechanical environment experienced by these devices is poorly understood. Furthermore, there are currently no studies that compare the performance of the different devices with regards to their long term positional stability (migration).