4D SSFP MRI for Detecting Functionally Important Coronary Artery Stenosis at Rest

4D SSFP MRI 用于检测静息时具有重要功能的冠状动脉狭窄

• 批准号: 7788128
• 负责人: Rohan Dharmakumar
• 金额: $ 37.14万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-04-15 至 2010-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7788128
• 关键词: Acute; Address; Adopted; Affect; Algorithms; Animal Model; Arteries; Blood Volume; Blood flow; Breathing; Canis familiaris; Cardiac; Cause of Death; Clinical; Clinical Management; Coronary Arteriosclerosis; Coronary Stenosis; Coronary artery; Detection; Development; Disease; Early Diagnosis; Goals; Heart; Human; Image; Imaging Techniques; Left ventricular structure; Life; Magnetic Resonance; Magnetic Resonance Imaging; Measures; Methods; Modeling; Monitor; Motion; Myocardial; Myocardium; Oxygen; Patients; Phase; Physiological; Procedures; Radial; Research; Rest; Risk; Signal Transduction; Staging; Stress; Techniques; Testing; Time; Treatment Efficacy; United States; Validation; Weight; base; clinically significant; coronary perfusion; functional disability; image registration; imaging modality; improved; outcome forecast; patient population; prevent; public health relevance; sudden cardiac death

DESCRIPTION (provided by applicant): Coronary artery disease is the leading cause of death in the United States. It is estimated that nearly 7 million people are living with coronary artery disease (CAD) in the US and about half a million people die from it each year. The most common form of CAD leads to narrowing of the coronary arteries (stenosis) resulting in reduced blood flow and oxygen supplied to the heart muscle. Accurate early detection of these functional impairments may permit interventional revascularization procedures to re-establish blood flow to the affected regions. The absence of revascularization increases the risk of sudden cardiac death. Currently there are no noninvasive methods that can accurately detect regional flow differences due to CAD. The broad and long term goal of this proposal is to accurately guide revascularization strategies and to monitor the efficacy of the treatment of coronary artery disease with magnetic resonance imaging (MRI). We propose a new method for detecting the presence of a clinically significant non flow-limiting coronary artery stenosis (defined as a decrease in coronary artery lumen radius by 70%). The proposed method relies on the use of cardiac phase-resolved steady-state free precession (SSFP) magnetic resonance (MR) signal changes originating from regional blood volume and oxygenation changes in the myocardial territory supplied by a stenotic artery. The principle advantage of this method over other MRI methods is that it can permit the detection of a functionally significant coronary stenosis under resting conditions, thereby eliminating the need to assess coronary perfusion reserve changes with pharmacological stress-inducing agents. The proposed project will be developed in three stages: (1) The first stage will consist of technical developments with the objective of developing a free-breathing, fast MR method for acquiring and evaluating cardiac phase-dependent SSFP signals over the whole heart. (2) The second stage of the project will use standard MR methods for evaluating phasic changes in myocardial blood volume and oxygenation independently using healthy canine models. The primary goal of this aim is to demonstrate that blood volume and oxygenation changes can be simultaneously detected with SSFP imaging in the same canine models with improved sensitivity. (3) The final stage of our proposal will focus on evaluating cardiac phase-resolved changes in myocardial blood volume and oxygenation in animal models with acute coronary stenosis. The goal of this study will be to demonstrate that the SSFP method provides enhanced sensitivity for simultaneously identifying changes in blood volume and oxygenation in a myocardial territory supplied by a stenotic coronary artery. These studies will provide the basis for identifying the presence of a functionally significant coronary stenosis in humans under resting conditions. PUBLIC HEALTH RELEVANCE: An accurate and noninvasive method for detecting clinically significant coronary artery disease can provide the necessary impetus for revascularization and prevent sudden cardiac deaths. This proposal presents a MRI-based method that has the potential to revolutionize the way cardiac exams aimed at detecting clinically significant coronary artery disease are performed in clinical settings with little or no patient discomfort. Most importantly, the proposed method has the potential to non-invasively detect coronary artery disease, guide initial treatment, and enable clinical management in patient populations with the disease.

描述（由申请人提供）：冠状动脉疾病是美国死亡的主要原因。据估计，美国有近700万人患有冠状动脉疾病（CAD），每年大约有50万人死亡。最常见的CAD形式导致冠状动脉（狭窄）变窄，导致血液流量减少，并提供给心脏肌肉的氧气。准确对这些功能障碍的早期检测可能允许介入的血运重建程序重新建立流向受影响区域的血液。缺乏血运重建会增加心脏猝死的风险。当前，尚无无创方法可以准确检测由于CAD引起的区域流量差异。该提案的广泛而长期的目标是准确指导血运重建策略，并通过磁共振成像（MRI）来监测冠状动脉疾病治疗的功效。我们提出了一种新方法，用于检测存在临床上显着的非流动冠状动脉狭窄的存在（定义为冠状动脉腔半径降低70％）。所提出的方法依赖于使用心脏相位分辨的稳态自由进动（SSFP）磁共振（MR）信号变化，源自区域血容量和狭窄动脉提供的心肌区域的氧合变化。该方法比其他MRI方法的原理优点是，它可以允许在静止条件下检测具有功能意义的冠状动脉狭窄，从而消除了与诱导药理学胁迫的剂量评估冠状动脉灌注储备的变化。拟议的项目将分为三个阶段：（1）第一阶段将包括技术发展，目的是开发自由呼吸，快速的MR方法，用于在整个心脏中获取和评估心脏相依赖的SSFP信号。 （2）项目的第二阶段将使用标准MR方法来评估使用健康的犬模型独立地独立于心肌血容量和氧合的阶段变化。此目的的主要目的是证明可以在具有提高灵敏度的同一犬模型中与SSFP成像同时检测血容量和氧合变化。 （3）我们提案的最后阶段将集中于评估具有急性冠状动脉狭窄的动物模型中心肌血容量和氧合的心脏相位变化。这项研究的目的是证明SSFP方法具有增强的灵敏度，以同时识别由狭窄冠状动脉提供的心肌区域中血容量和氧合的变化。这些研究将为识别在静止条件下人类中功能意义的冠状动脉狭窄的存在提供基础。公共卫生相关性：一种用于检测临床意义的冠状动脉疾病的准确且无创的方法，可以为血运重建和预防心脏突然死亡提供必要的动力。该提案提出了一种基于MRI的方法，该方法有可能彻底改变旨在检测临床意义的冠状动脉疾病的心脏检查方式，在临床环境中很少或没有患者不适。最重要的是，该提出的方法具有非侵入性检测冠状动脉疾病的潜力，引导初始治疗以及能够在患有该疾病的患者人群中进行临床管理。