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）影响超过500万美国人，是死亡的主要原因和住院治疗的最常见原因。近50%的CHF患者将在诊断后5年内死亡，这比大多数癌症的死亡率更高。心脏起搏治疗（CRT）已成为CHF伴不同步患者的一种有前景的治疗方法，试验表明，当成功放置起搏器电极导线时，CRT可显著改善症状和心脏泵效率。目前，仅使用X射线成像来指导CRT的起搏器电极导线的放置，但这种方式几乎不能为医生提供功能和解剖信息。通过相对“盲目”转向进行电极导线放置，这导致20%的手术失败率，并可能解释超过30%的无应答率。另一方面，MRI提供了独特的软组织对比度，无需使用电离辐射来描绘冠状静脉形态，量化心肌不同步性，并识别疤痕组织。人们普遍认为，这些因素是CRT临床结局的关键决定因素，应将其用于患者选择、手术计划和CRT指导。本项目的目的是开发一种“X射线融合MR”（XFM）图像引导系统，用于将术前MR衍生静脉成像、机械不同步和心肌活力与术中X射线图像整合在一起，以指导CRT手术。这些措施将允许医生在电极导线放置过程中实时将冠状静脉和左心室电极导线的位置与周围软组织特征直接关联。我们假设，这种XFM引导系统将有助于更有效地放置起搏器电极导线，最终导致CRT应答率增加。该项目将分为三个主要具体目标：（1）开发一种心脏MR成像方法，用于创建冠状静脉解剖结构、机械不同步，和心肌活力（2），以开发XFM介入引导系统，该系统在EP实验室（3）中提供实时X射线图像上MR衍生测量的实时叠加，并补偿呼吸运动通过体内动物实验验证XFM CRT系统，然后进行首次人体临床研究。该项目将汇集独特的MR成像方法和最先进的介入图像引导，以解决美国的主要死亡原因之一。公共卫生相关性：充血性心力衰竭（CHF）影响超过500万美国人，并且是死亡的主要原因和住院的最常见原因。心脏起搏治疗（CRT）已成为CHF伴不同步患者的一种有前景的治疗方法，试验表明，当成功放置起搏器电极导线时，CRT可显著改善症状和心脏泵效率。今天，仅使用X射线成像来指导CRT的起搏器电极导线的放置，但是这种方式向医生提供的功能和解剖信息很少，这可以解释超过30%的无应答率。本项目的目的是开发一种“X射线融合MR”（XFM）图像引导系统，用于整合术前MRI衍生静脉成像、机械不同步和心肌活力与术中X射线图像，以指导CRT手术，目的是提高患者反应率。

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.