Lakatos Bálint, Tősér Zoltán, Tokodi Márton, Doronina Alexandra, Kosztin Annamária, Muraru Denisa, Badano Luigi P, Kovács Attila, Merkely Béla
MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, Városmajor St. 68, H-1122, Budapest, Hungary.
Department of Software Technology and Methodology, Eötvös Loránd University, Budapest, Hungary.
Cardiovasc Ultrasound. 2017 Mar 27;15(1):8. doi: 10.1186/s12947-017-0100-0.
Three major mechanisms contribute to right ventricular (RV) pump function: (i) shortening of the longitudinal axis with traction of the tricuspid annulus towards the apex; (ii) inward movement of the RV free wall; (iii) bulging of the interventricular septum into the RV and stretching the free wall over the septum. The relative contribution of the aforementioned mechanisms to RV pump function may change in different pathological conditions.Our aim was to develop a custom method to separately assess the extent of longitudinal, radial and anteroposterior displacement of the RV walls and to quantify their relative contribution to global RV ejection fraction using 3D data sets obtained by echocardiography.Accordingly, we decomposed the movement of the exported RV beutel wall in a vertex based manner. The volumes of the beutels accounting for the RV wall motion in only one direction (either longitudinal, radial, or anteroposterior) were calculated at each time frame using the signed tetrahedron method. Then, the relative contribution of the RV wall motion along the three different directions to global RV ejection fraction was calculated either as the ratio of the given direction's ejection fraction to global ejection fraction and as the frame-by-frame RV volume change (∆V/∆t) along the three motion directions.The ReVISION (Right VentrIcular Separate wall motIon quantificatiON) method may contribute to a better understanding of the pathophysiology of RV mechanical adaptations to different loading conditions and diseases.
右心室（RV）泵功能主要由三种机制促成：（i）纵轴缩短，三尖瓣环向心尖牵引；（ii）右心室游离壁向内移动；（iii）室间隔凸入右心室并使游离壁在室间隔上伸展。上述机制对右心室泵功能的相对贡献在不同病理状态下可能会发生变化。我们的目的是开发一种定制方法，以分别评估右心室壁纵向、径向和前后位移的程度，并使用超声心动图获得的三维数据集量化它们对右心室整体射血分数的相对贡献。相应地，我们以基于顶点的方式分解导出的右心室袋状壁的运动。在每个时间帧，使用带符号四面体法计算仅在一个方向（纵向、径向或前后）上占右心室壁运动的袋状结构的体积。然后，右心室壁沿三个不同方向运动对右心室整体射血分数的相对贡献，既可以计算为给定方向的射血分数与整体射血分数之比，也可以计算为沿三个运动方向的逐帧右心室容积变化（∆V/∆t）。ReVISION（右心室壁独立运动量化）方法可能有助于更好地理解右心室对不同负荷条件和疾病的机械适应性的病理生理学。
