C-Arm CT for Guidence of Cardiac Interventions

描述(申请人提供)：在X射线透视引导下使用血管内通路的微创心脏手术使以前需要心内直视手术的患者得以治疗。这种微创手术因其风险较低、恢复较快和成本较低而受到青睐。增长最快的手术之一是消融治疗心房颤动--这个问题最终为20%的人口所困扰，也是导致中风、患者发病率和死亡率的重要因素。虽然前景看好，但第一次介入的手术成功率仍然只有~50%，即使是随后的介入，最终结果的成功率也徘徊在~70%。据推测，造成成功率有限的一个主要因素是缺乏对所产生的病变的确切数量和位置的准确了解。我们建议利用和扩展我们的心电门控心脏C臂CT的最新发展，以在介入过程中提供三维成像。通过利用介入套件中的X射线系统生成3D图像，将避免与先前的CT或MRI检查进行容易出错和耗时的时空配准。反映患者当前状态的详细三维图像将与电解剖图相结合，以最佳地帮助干预者。我们的目标也是通过缩短透视引导所需的时间和采用多维降噪算法来减少对患者和工作人员的辐射剂量。我们将通过解决欠采样、采集时间和时间清晰度问题，以及通过开发硬件和软件来提高低对比度性能、配准精度和可视化，来提高图像质量。我们的目标之一是展示显示左心房和肺静脉的能力，以提供优于2 mm的指导精度，并将注册所需的时间减少50%(~20分钟)。有了这些进展，我们的最终目标是以与外科手术相同的成功率(80%-90%)完成更快、更准确的导管介入治疗。该项目的重要性进一步扩大，因为所开发的技术最终可能会影响许多当前的其他微创程序，以及未来可用的程序，例如用于治疗心肌梗死的心内膜干细胞注射。项目简介该项目旨在提供介入过程中介入套间心脏跳动的高质量3D CT图像。我们相信，提供反映介入时患者真实状态的图像，与设备跟踪硬件相结合，将显著提高准确性，并减少射频消融等复杂程序的操作时间。我们还在开发新的图像处理和重建方法，可以对心脏壁内的射频病变进行3D可视化，从而可以在术中监测病变的位置。在介入过程中获得这样的图像，也可以通过允许准确地指导治疗(细胞、药物等)来实现新的、直接的心肌梗死治疗。直接到达受影响的组织。

DESCRIPTION (provided by applicant): Minimally invasive cardiac procedures using endovascular access under x-ray fluoroscopic guidance have enabled treatment of patients that previously would have required open-heart surgery. Such minimally invasive procedures are preferred because of their lower risk, faster recovery and lower cost. One of the fastest growing procedures is ablation for treatment of atrial fibrillation - a problem eventually suffered by 20% of the population and a significant contributor to stroke, patient morbidity and mortality. While promising, procedure success rates are still only ~50% for the first intervention, and even with subsequent interventions, final outcome success hovers at ~70%. It is hypothesized that a major factor contributing to the limited success rate is the lack of precise knowledge about the exact number and location of the created lesions. We propose to leverage and expand upon our recent development of ECG gated cardiac C-arm CT to provide three-dimensional imaging during the interventional procedure. By generating 3D images utilizing the x-ray system in the interventional suite, the error prone and time-consuming spatio-temporal registration with prior CT or MRI exams will be avoided. Detailed three- dimensional images reflecting the current state of the patient will be combined with electroanatomical maps to optimally assist the interventionalist. We aim to also reduce the radiation dose to both patients and staff by shortening the time needed for fluoroscopic guidance and by incorporating multi-dimensional noise reduction algorithms. We will develop image quality improvements by addressing under-sampling, acquisition timing and temporal definition, and by developing hardware and software to improve low-contrast performance, registration accuracy and visualization. One of our goals is to demonstrate the ability to depict the left atrium and pulmonary veins to provide guidance accuracy of better then 2 mm, and to reduce the time required for registration by 50% (~20 minutes). With these developments our ultimate goal is to accomplish faster and more accurate catheter based interventions with an equivalent success rate as surgical procedures (80-90%). The significance of this project is further amplified by the fact that the technology developed could eventually impact many other current minimally invasive procedures, and also future procedures as they become available, such as endocardial injection of stem cells for treatment of myocardial infarction. Project Narrative The project aims to provide high-quality 3D CT images of the beating heart in the interventional suite during an interventional procedure. We believe that providing images that reflect the true status of the patient at the time of intervention, when combined with device-tracking hardware, will provide significant improvements in accuracy and reduction in procedure times for complicated procedures such as radiofrequency ablation of atrial fibrillation. We are also developing new image processing and reconstruction approaches that may permit 3D visualization of radiofrequency lesions in the heart wall that would allow intra-procedural monitoring of lesion placement. Access to such images, during an interventional procedure, could also enable new, directed treatments for myocardial infarction by allowing accurate guidance of therapy (cell, drug etc.) directly to the affected tissue.