Defining 4D Ventricular Mechanics in Acquired and Congenital Heart Disease

描述（由申请人提供）： 包括心脏起搏在内的心力衰竭积极治疗的迅速采用，重新引起了人们对左心室基本机电特性的兴趣。与MRI相关，这导致了旨在开发和应用评估左心室力学的方法的研究工作，包括磁共振组织标记、相位速度心肌标测和3D空间中的电影DENSE位移标测。相比之下，研究右心室力学的努力较少，即使在某些情况下，如先天性心脏病，肺动脉高压和肺心病，RV功能可能比LV功能更重要。 在超声心动图中，组织多普勒应变率方法的发展现在已经被更新的斑点跟踪方法所遵循，该方法能够显示多种类型的应变变形而没有角度依赖性，包括收缩期的周向缩短应变、径向增厚应变以及扭转和解扭转。二维方法可以在一定程度上定义横截面视图中的节段运动，但是通过平面运动来复合。对于回波和MRI，可能需要强大的3D方法来全面定义局部心室壁运动和变形。 该提案旨在开发和验证一种方法，以通过在高级3D超声心动图系统上进行的超声扫描获得左心室和右心室变形图的空间密集位移场;该方法应能够显示两个心室的应变位移场和扭转变形。该提案旨在进一步发展我们开创的技术，并在独特的动态心脏体模和开胸猪中使用声显微测量法作为金标准对其进行验证。我们还将评估我们的新方法的有效性，并通过研究先天性心脏病患者将其转化为临床环境，并比较我们的方法MRI标记和室壁速度编码应变测量的结果。 公共卫生相关性： 心脏病学对最近开发的用于心脏成像的4D超声技术非常感兴趣。我们认为，这些动态定性解剖诊断图像信息丰富，这些用于定义心脏力学的4D方法的定量方面可能更重要。我们已经开发并希望在本提案中进一步完善和测试的空间密集4D斑点跟踪方法可以提供用于研究心脏的动态双心室功能的方法，这反过来可以改善治疗心脏疾病的治疗方法。

DESCRIPTION (provided by applicant): The rapid adoption of aggressive treatments for heart failure, including resynchronization pacing, has renewed interest in the fundamental electromechanical properties of the left ventricle. Related to MRI, this has resulted in research efforts aimed at the development and application of methods to assess left ventricular mechanics, including magnetic resonance tissue tagging, phase velocity myocardial mapping and cine DENSE displacement mapping in 3D space. By comparison, there have been fewer efforts to study right ventricular mechanics, even though in certain conditions such as congenital heart diseases, pulmonary hypertension and cor pulmonale, RV function can be more important than LV function. In echocardiography, the development of tissue Doppler strain rate methods have been by now followed by newer speckle tracking methods capable of showing multiple types of strain deformation without angle dependency, including circumferential shortening strain, radial thickening strain in systole and twisting and untwisting. Two-dimensional methods can define, to some extent, segmental motion in cross-sectional views, but are compounded by through-plane motion. For both echo and MRI, it will likely require a robust 3D method to comprehensively define regional ventricular wall motion and deformation. This proposal is aimed at development and validation of a method to obtain spatially-dense displacement fields of both left and right ventricular deformation maps from ultrasound scans performed on an advanced 3D echocardiographic system; a method that should be capable of showing strain displacement fields and torsional deformation for both ventricles. This proposal is aimed at further developing the techniques we have pioneered and validating them in a unique dynamic cardiac phantom and in open-chest pigs using sonomicrometry as a gold standard. We will also evaluate the efficacy of our new approach and translate it to the clinical setting by studying patients with congenital heart disease and compare our results from our method MRI tagging, and wall velocity encoded strain measurements. PUBLIC HEALTH RELEVANCE: Much interest exists in Cardiology in the recently developed 4D ultrasound technologies for imaging the heart. We believe that as informative as these dynamic qualitative anatomical diagnostic images are, the quantitative aspects of these 4D methods for defining cardiac mechanics are likely more important. The spatially-dense 4D speckle tracking method which we have developed and hope to further refine and test in this proposal could provide a method for study of the dynamic biventricular function of the heart, which could, in turn, improve therapeutic approaches to treatment of heart disease.