Automatic quantification of myocardial motion in older adults

摘要 心力衰竭 (HF) 是一种常见病症，代表心血管疾病 (CVD) 的末期 在进行性心肌损伤或缺血之后。在 65 岁及以上的人群中，冠心病 动脉疾病（CAD）是心力衰竭的主要原因。尽管左心室 (LV) 射血分数较低 (EF)是临床上诊断心力衰竭的主要证据，受损的局部心肌功能障碍是 预计将在早期阶段展示 CAD 的存在。 心脏变形分析（HDA）是一种尖端的心肌运动分析技术，能够 自动跟踪时间范围内的心肌边界并计算全局和区域心脏 无需额外扫描即可对现有电影图像进行功能和运动索引。在本研究中，我们将使用 HDA 工具用于分析 CHARISMA 研究的现有电影图像。 2009年至2012年心脏MRI检查 （包括冠状动脉壁成像和两腔、四腔和短轴视图的电影 MRI）和 对 440 名老年参与者（年龄：65 - MRI 扫描时年龄为 84 岁），没有记录的 CVD 病史。在目前的R03项目期间 （2019-2021），CHARISMA 参与者将被随访 10 - 12 年。我们计划新联系- 获得的局部心肌运动指数（位移、速度、应变和应变率）用于临床 CHARISMA 数据集中的结果、现有冠状动脉测量和实验室测试结果。我们将测试 总体假设是，局部心肌运动指数有可能在以下人群中呈现心血管风险： 无症状老人。三个具体目标是： 1) 使用基线区域预测心血管事件 心肌运动指数； 2) 将局部心肌运动指数与 MRI 衍生的冠状动脉特征相关联 改造； 3) 确定局部心肌运动指数与传统心肌运动指数之间的相关性 CHARISMA 研究中收集的心血管风险生物标志物/状况。 该项目不需要新的 MRI 扫描或实验室测试。通过具有成本效益的方法，立即 该项目的目的是评估局部心肌运动的临床价值 无症状老年人（心血管疾病的主要目标人群）的心血管风险分层 预防。这项研究还将帮助我们更好地了解受损心肌之间的相关性 功能/运动和亚临床 CAD 负担。此外，结果将有助于定量选择 成像生物标志物及其预测未来临床心血管事件的最佳截止点 研究。

Abstract Heart failure (HF) is a common condition that represents the end stage of cardiovascular diseases (CVDs) subsequent to progressing myocardial damage or ischemia. In populations at ages 65 and older, coronary artery disease (CAD) serves as the leading cause of HF. Although low left ventricular (LV) ejection fraction (EF) is a major evidence for the diagnosis of HF in clinical practice, impaired regional myocardial dysfunction is expected to present the existence of CAD in its early stage. Heart deformation analysis (HDA) is a cutting-edge myocardial motion analysis technique that is able to automatically track the myocardium borders on time frames and calculate global and regional cardiac functional and motional indices on existing cine images without extra scans. In the present study, we will use the HDA tool to analyze existing cine images of CHARISMA study. From 2009 to 2012, cardiac MRI exams (including coronary wall imaging and cine MRI at two-chamber, four-chamber and short-axis views) and concurrent tests for traditional cardiovascular risk factors were performed on 440 older participants (age: 65 - 84 years old at the time of MRI scans) without documented history of CVDs. During the present R03 project (2019-2021), CHARISMA participants would have been followed-up for 10 - 12 years. We plan to relate newly- acquired regional myocardial motion indices (displacement, velocity, strain and strain rate) to clinical outcomes, existing coronary wall measures and results of lab tests in CHARISMA datasets. We will test the overall hypothesis that regional myocardial motion indices have the potential to present cardiovascular risk in asymptomatic elderly. Three specific aims are: 1) Predict cardiovascular events using baseline regional myocardial motion indices; 2) Relate regional myocardial motion indices to MRI-derived features of coronary remodeling; and 3) Determine correlations between regional myocardial motion indices and traditional cardiovascular risk biomarkers/conditions collected in CHARISMA study. No new MRI scans or lab tests are required in this project. Through a cost-effective approach, the immediate objective of the proposed project is to evaluate the clinical value of regional myocardial motion for cardiovascular risk stratification in asymptomatic older adults, a major target population of cardiovascular prevention. This study will also help us better understand the correlations between impaired myocardial function/motion and subclinical CAD burden. Furthermore, the results will facilitate the selection of quantitative imaging biomarkers and their optimal cut-off points for predicting cardiovascular events in future clinical studies.