An XFM Interventional Guidance System for Cardiac Resynchronization Therapy

描述（由申请人提供）：充血性心力衰竭（CHF）影响着超过500万美国人，是导致死亡的主要原因，也是住院治疗的最常见原因。近50%的慢性心力衰竭患者将在确诊后的5年内死亡，这比大多数癌症的死亡率都要高。心脏再同步化治疗（CRT）已成为治疗伴有非同步化的CHF患者的一种很有前景的治疗方法，试验表明，当起搏器导联成功放置时，可显著改善症状和心脏泵效率。今天，x射线成像仅用于引导CRT起搏器导联的放置，但这种方式为医生提供的功能和解剖信息很少。引线放置是通过相对“盲目”的操作进行的，这导致了20%的程序失败率，并可能解释了超过30%的无反应率。另一方面，MRI在不使用电离辐射的情况下提供独特的软组织对比，以描绘冠状静脉形态，量化心肌非同步化和识别疤痕组织。人们普遍认为，这些因素是CRT临床结果的关键决定因素，它们应用于患者选择，程序规划和CRT指导。该项目的目的是开发一种“x射线与磁共振融合”（XFM）图像引导系统，将术前磁共振衍生静脉成像、机械非同步化和心肌活力与术中x射线图像结合起来，指导CRT程序。这些措施将使医生能够直接将冠状静脉和左心室导联的位置与导联放置过程中周围软组织的实时特征联系起来。我们假设这种XFM引导系统将有助于更有效地放置起搏器导联，最终导致CRT应答率的增加。该项目将分为三个主要的具体目标：(1)开发一种心脏MR成像方法，用于创建冠状静脉解剖、机械非同步化和心肌活力的单一3D表示(2)开发一种XFM介入引导系统，在EP实验室中提供实时覆盖实时x射线图像的MR衍生测量，并补偿呼吸运动(3)通过体内动物实验验证XFM CRT系统，随后进行首次人体临床研究。该项目将汇集独特的磁共振成像方法和最先进的介入图像指导，以解决美国主要的死亡原因之一。公共卫生相关性：充血性心力衰竭（CHF）影响着超过500万美国人，是导致死亡的主要原因，也是住院治疗的最常见原因。心脏再同步化治疗（CRT）已成为治疗伴有非同步化的CHF患者的一种很有前景的治疗方法，试验表明，当起搏器导联成功放置时，可显著改善症状和心脏泵效率。如今，x射线成像仅用于引导CRT中起搏器导联的放置，但这种方式向医生提供的功能和解剖信息很少，这可能解释了超过30%的无反应率。该项目的目标是开发一种“x射线与磁共振融合”（XFM）图像引导系统，将术前mri衍生的静脉成像、机械非同步化和心肌活力与术中x射线图像结合起来，指导CRT程序，目的是提高患者的反应率。

DESCRIPTION (provided by applicant): Congestive heart failure (CHF) affects over 5 million Americans and is a major cause of death and the most common reason for hospitalization. Nearly fifty percent of CHF patients will die within 5 years of diagnosis, which is a higher mortality than most forms of cancer. Cardiac resynchronization therapy (CRT) has emerged as a promising therapy for CHF patients with dyssynchrony and has been shown in trials to significantly improve symptoms and cardiac pump efficiency when pacemaker leads are placed successfully. Today, X-ray imaging alone is used to guide placement of pacemaker leads for CRT, but this modality provides little functional and anatomic information to the physician. Lead placement is performed by steering relatively "blindly" which contributes to a procedural failure rate of 20% and may explain a non-response rate of more than 30%. On the other hand, MRI offers unique soft tissue contrast without the use of ionizing radiation for depicting coronary vein morphology, quantifying myocardial dyssynchrony, and identifying scar tissue. It is widely believed that these elements are key determinants of clinical outcomes for CRT and that they should be used for patient selection, procedural planning, and guidance of CRT. The objective of this project is to develop an "X-ray fused with MR" (XFM) image guidance system for integrating pre-procedural MR-derived vein imaging, mechanical dyssynchrony and myocardial viability with intra-procedural X-ray images to guide CRT procedures. These measures will allow the physician to directly relate the positions of the coronary vein and left ventricular leads with the surrounding soft tissue characteristics in real-time during lead placement. We hypothesize that this XFM guidance system will facilitate more effective placement of the pacemaker leads, ultimately leading to an increase in CRT responder rates. This project will be divided into three main Specific Aims: (1) to develop a cardiac MR imaging methodology for creating a single 3D representation of coronary vein anatomy, mechanical dyssynchrony, and myocardial viability (2) to develop an XFM interventional guidance system that provides real-time overlay of MR derived measures on live X-ray images with compensation of respiratory motion in the EP lab (3) to validate XFM CRT system with in vivo animal experiments followed by first in human clinical study. This project will bring together unique MR imaging methods and state of the art interventional image guidance to address one of the leading causes of death in the United States. PUBLIC HEALTH RELEVANCE: Congestive heart failure (CHF) affects over 5 million Americans and is a major cause of death and the most common reason for hospitalization. Cardiac resynchronization therapy (CRT) has emerged as a promising therapy for CHF patients with dyssynchrony and has been shown in trials to significantly improve symptoms and cardiac pump efficiency when pacemaker leads are placed successfully. Today, X-ray imaging alone is used to guide placement of pacemaker leads for CRT, but this modality provides little functional and anatomic information to the physician, which may explain a non-response rate of more than 30%. The objective of this project is to develop an "X-ray fused with MR" (XFM) image guidance system for integrating pre-procedural MRI-derived vein imaging, mechanical dyssynchrony and myocardial viability with intra- procedural X-ray images to guide CRT procedures, with the goal of improving patient response rates.