Early Detection and Mapping of Ischemia using Myocardial Elastography

 描述(申请人提供)：心血管疾病仍然是美国的主要杀手，夺走的美国人的生命超过了紧随其后的两个主要死因(癌症和肺部并发症)的总和。特别是，到目前为止，冠状动脉疾病(CAD)是最致命的，每年导致的死亡(无论是否与心脏相关)占所有死亡人数的17%。死亡人数如此之高的主要原因之一是严重缺乏有效和可获得的成像工具来检测心电图异常，特别是在冠心病可以通过适当的药物治疗稳定下来的早期阶段。我们研究的长期目标是建立一种低成本、便携、非侵入性和可靠的潜在 本课题组首创的心肌弹性图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确定的所有限制，并确保检测的临床翻译 脑缺血和与脑梗塞的鉴别。我们团队是第一个证明使用并行波束成形的心脏应变成像是可行的1)在极高的帧速率(高达2000 fps)下确保2)高精度和3)角度无关的2D应变估计，3)3D能力，4)瞬时心脏事件的成像(~1-10 ms机电应变)和5)实时实施6)不需要心电门控或屏气。因此，这项研究的假设是，平行波束成形心肌弹性成像(PBME)将在以下方面提高敏感性：1)检测当前方法可能遗漏的早期缺血发作；2)基于由此引起的机械和电动机械心功能的改变，区分早期发作和晚期缺血或梗塞。其具体目的如下：1)在模拟和模体中表征PBME的基本性能；2)验证PBME对活体犬早期发病的检测；以及3)对照CT血管成像和核灌注验证PBME的结果。PBME在检测和表征早期缺血发作方面的高可靠性将使其易于转换并无缝集成到临床超声心动图常规中。

 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.