Dennig K, Nesser H J, Haase H U, Schömig A
Deutsches Herzzentrum and 1. Medizinische Klinik, Technische Universität München, Munich, Germany.
J Am Soc Echocardiogr. 2001 May;14(5):343-52. doi: 10.1067/mje.2001.109985.
Determination of ventricular filling volumes with the use of Doppler echocardiographic measurements critically depends on the presence of a circular-shaped flow area and a flat velocity profile across it because evaluation of flow volume is usually based on echocardiographic measurements of its diameter and pulsed Doppler recordings within the center of this area. The approach may be limited at the mitral and tricuspid ring levels as a result of their noncircular shape and because nonflat velocity profiles are present. The purpose of this study was to examine in a pulsatile flow model simulating ventricular inflow conditions the accuracy of an automated method based on the analysis of color Doppler flow velocities for evaluation of flow volumes.
A recently-developed automated Doppler method that takes into account the velocity distribution across a region of interest was examined in a pulsatile flow model by using flows with waveforms characteristic for ventricular inflow through tubes with elliptically-shaped cross-sectional areas. Color Doppler imaging was performed against flow direction along the major and minor axes of the tubes with major diameters ranging between 3 and 5 cm and major-to-minor diameter ratios of 1.5 and 2.0.
A close correlation was found between flow volumes measured by the Doppler technique for registrations along the minor or major axis of the ellipses and actual values (r = 0.99, standard error of the estimate = 0.44 to 1.98 mL), with a systematic underestimation or overestimation, respectively, depending on the diameter ratio. Averaging of the data derived from 2 orthogonal measurements by using the geometric mean value yielded an excellent agreement between Doppler data and actual flow volumes.
This automated color Doppler method enables reliable determination of flow volumes in a pulsatile flow model simulating ventricular inflow conditions with the use of 2 orthogonal imaging views. The data indicate that the method may improve the noninvasive evaluation of ventricular filling volumes.
使用多普勒超声心动图测量来确定心室充盈容积，关键取决于是否存在圆形的血流区域以及该区域上平坦的速度分布，因为血流量的评估通常基于对该区域直径的超声心动图测量以及该区域中心内的脉冲多普勒记录。由于二尖瓣和三尖瓣环水平的形状不是圆形且存在非平坦的速度分布，这种方法在这些水平可能会受到限制。本研究的目的是在模拟心室流入情况的脉动流模型中，检验一种基于彩色多普勒血流速度分析的自动方法用于评估血流量的准确性。
在一个脉动流模型中，通过使用具有心室流入特征波形的血流，流经具有椭圆形横截面的管道，对一种最近开发的考虑感兴趣区域速度分布的自动多普勒方法进行了检验。沿管道的长轴和短轴方向进行彩色多普勒成像，管道的大直径范围在3至5厘米之间，长径与短径之比为1.5和2.0。
对于沿椭圆短轴或长轴记录的多普勒技术测量的血流量与实际值之间发现了密切相关性（r = 0.99，估计标准误差 = 0.44至1.98毫升），根据直径比分别存在系统性低估或高估。通过使用几何平均值对来自两个正交测量的数据进行平均，得到多普勒数据与实际血流量之间的极佳一致性。
这种自动彩色多普勒方法能够在使用两个正交成像视图的模拟心室流入情况的脉动流模型中可靠地确定血流量。数据表明该方法可能会改善心室充盈容积的无创评估。
