Early Detection and Mapping of Ischemia using Myocardial Elastography

 描述（由申请人提供）：心血管疾病仍然是美国的主要杀手，在很大程度上，夺去更多美国人的生命，而不是接下来的两个主要死亡原因（癌症和肺部并发症）的总和。特别是，冠状动脉疾病（CAD）是迄今为止最致命的，每年造成17%的所有（心脏相关或非）死亡。这种高死亡率的主要原因之一是在心电图（ECG）上检测到异常时严重缺乏有效和可访问的成像工具，特别是在CAD可以通过适当的药理学方案稳定的早期阶段。我们研究的长期目标是建立一种低成本、便携式、非侵入性和可靠的 本课题组首创的心肌弹性成像应变成像技术，用于心肌缺血的早期检测和定位。在这项更新研究中，我们建议克服在过去资助期间发现的所有限制，并确保临床转化为检测 与梗死的鉴别。我们的小组是第一个证明使用并行波束形成的心脏应变成像是可行的1）在极高的帧速率（高达2000 fps）确保2）高精度和3）与角度无关的2D应变估计，3）3D功能，4）瞬时心脏事件的成像（~1-10 ms机电应变）和5）实时实现6）没有ECG门控或屏气。因此，本研究的假设是平行波束形成心肌弹性成像（PBME）将具有增加的灵敏度，用于1）检测当前模态可能遗漏的缺血早期发作，以及2）基于所产生的机械和机电心脏功能改变区分早期发作与晚期缺血或梗死。具体目标如下：1）表征模拟和体模中PBME的基本性能; 2）验证体内犬早期疾病发作的PBME检测; 3）验证PBME结果与CT血管造影和核灌注。PBME用于早期缺血发作的检测和表征的高可靠性将需要其在临床超声心动图常规中的容易翻译和无缝集成。

 DESCRIPTION (provided by applicant): Cardiovascular diseases remain America's primary killer by a large margin, claiming the lives of more Americans than the next two main causes of death combined (cancer and pulmonary complications). In particular, coronary artery disease (CAD) is by far the most lethal, causing 17% of all (cardiac-related or not) deaths every year. One of the main reasons for this high death toll is the severe lack of effective and accessible imaging tools upon anomaly detected on the electrocardiogram (ECG), especially at the early stages when CAD can be stabilized with appropriate pharmacological regimen. The long-term goal of our studies is to establish the potential of a low-cost, portable, noninvasive and reliable strain imaging technique of Myocardial Elastography pioneered by our group for early detection and localization of myocardial ischemia. In this renewal study, we propose to overcome all limitations identified during the past funding period and ensure clinical translation for detection of ischemia and differentiation from infarction. Our group was the first to demonstrate that cardiac strain imaging using parallel beamforming is feasible 1) at extremely high frame rates (up to 2000 fps) ensuring 2) high precision and 3) angle-independent 2D strain estimates, 3) 3D capability, 4) imaging of transient cardiac events (~1-10 ms electromechanical strains) and 5) real-time implementation 6) without ECG gating or breath holds. Therefore, the hypothesis of this study is that parallel- beamforming Myocardial Elastography (PBME) will have increased sensitivity for 1) detection of early onset of ischemia that current modalities may miss and 2) differentiation of early onset from advanced ischemia or infarction based on the resulting altered mechanical and electromechanical cardiac function. The specific aims are as follows: 1) characterize fundamental performance of PBME in simulations and phantoms; 2) validate PBME detection of early disease onset in canines in vivo; and 3) validate PBME findings against CT angiography and nuclear perfusion. High reliability of PBME for detection and characterization of early ischemic onset would entail its readily translation and seamless integration in the clinical echocardiography routine.