Novel Echocardiographic Methods to Characterize Heart Failure in ESRD

 描述（由申请方提供）：一般人群中心力衰竭的当前范例不能充分描述终末期肾病（ESRD）患者的心脏疾病谱。大多数ESRD患者的左心室射血分数正常，舒张功能轻度受损，通过常规超声心动图方法测量。这些信息表明，大多数ESRD患者发生心力衰竭的风险较低。事实上，透析患者的心力衰竭和心血管死亡率极高。我们相信，现代超声心动图方法将在这一人群中捕获更广泛的收缩和舒张功能，从而更好地了解心脏功能和风险。研究该人群心力衰竭的另一个挑战是血液透析相关的容量状态变化对心功能的影响。本研究的目的是使用两种新方法收集与血液透析相关的时间一致的超声心动图数据。心室腔弹性（刚度）是一种新的参数，可以使用常规超声心动图图像的定量分析无创计算，并被认为是独立的负载条件。斑点跟踪超声心动图是一种最先进的成像和分析模式，其捕获收缩期和舒张期期间单个心脏节段的增量变形，因此是内在心肌力学的测量，而不是依赖于心室容积的全局心腔测量（例如射血分数）。超声心动图将在作为K23奖的一部分招募的ESRD队列中进行，该奖项专注于ESRD中的血管功能障碍。我们将研究200名接受血液透析的参与者;患者将在本周第一次透析后的第二天接受研究。还将在透析日（透析前后）对20例患者进行研究，以检验新的回波参数在透析期间的变化小于传统的体积依赖性参数的假设。我们将严格裁定心力衰竭住院治疗，区别于因医疗不依从或错过透析而住院治疗。我们将比较新型和传统超声心动图在预测两年心力衰竭住院和总死亡率方面的性能。

 DESCRIPTION (provided by applicant): The current paradigm for heart failure in the general population does not adequately describe the spectrum of cardiac disease in patients with end-stage renal disease (ESRD). Most patients with ESRD have normal left ventricular ejection fraction and mildly impaired diastolic function, as measured by conventional echocardiographic methods. This information suggests that most patients with ESRD have low risk for heart failure. In fact, patients on dialysis have an extremely high rate of heart failure and cardiovascular mortality. We believe that modern methods of echocardiography will capture a broader range of systolic and diastolic function in this population, and thus provide better insight into cardiac function and risk. Another challenge in studying heart failure in this population is the impact tha hemodialysis-related changes in volume status have on cardiac function. The aim of this study is to collect echocardiographic data with consistent timing relative to hemodialysis, using two novel methods. Ventricular chamber elastance (stiffness) is a novel parameter that can be calculated non-invasively using quantitative analysis of conventional echocardiographic images, and is thought to be independent of loading conditions. Speckle tracking echocardiography is a state-of-the-art imaging and analysis modality that captures incremental deformation of individual cardiac segments during systole and diastole and thus is a measure of intrinsic myocardial mechanics as opposed to global cardiac chamber measurements (such as ejection fraction) that depend on ventricular volumes. Echocardiography will be performed in an ESRD cohort that is being recruited as part of a K23 Award focused on vascular dysfunction in ESRD. We will study 200 participants on hemodialysis; patients will be studied the day after their first dialysis session of the week. Twenty of the patients will also be studied on a dialysis day, directly before and after dialysis, to test the hypothesis that novel echo parameters will vary les during dialysis than traditional, volume-dependent parameters. We will rigorously adjudicate heart failure hospitalizations distinct from hospitalizations due to medical non-compliance or missed dialysis. We will compare the performance of novel and conventional echocardiography for predicting two-year heart failure hospitalizations and overall mortality.