Nozaki S, Shandas R, DeMaria A N
Division of Cardiovascular Medicine, UCSD Medical Center, University of California at San Diego 92108-8411, USA.
Am Heart J. 1997 Jan;133(1):19-28. doi: 10.1016/s0002-8703(97)70243-6.
The examination conditions necessary for accurate measurement of regurgitant volume by the proximal flow convergence method applying a simple hemispheric equation remain uncertain. This study investigated the requirement for measuring regurgitant stroke volume from the combined continuous-wave and color Doppler proximal flow convergence approach. Twenty-five pulsatile flow rates were produced by driving five regurgitant stroke volumes ranging from 30 to 70 ml/beat through planar orifices with cross-sectional areas ranging from 0.10 to 1.0 cm2. Four different shaped orifices (circular, rectangular with a major/minor axis ratio 2:1, slitlike with a major/minor axis ratio of 8:1, and square) having identical orifice areas (0.5 cm2) were examined. Regurgitant volume (RV) was estimated from the combined continuous-wave and color Doppler approach according to the previously described equation RV = 2 pi x (r max)2 x AV x (TVI/Vmax), where r max is maximal radial distance, AV is aliasing velocity, TVI is time velocity integral of regurgitant jet, and Vmax is peak velocity of regurgitant jet. Plotting the difference between actual and calculated RV versus radial distance of the proximal convergence shell for each flow rate from circular to rectangular orifices yielded curves conforming to a curvilinear function that crossed the point of zero difference at 1.0 cm. However, in the slitilke orifice, a more remote distance (1.6 cm) is required for the best agreement. Actual regurgitant stroke volume can be estimated well by the combined continuous-wave Doppler and proximal flow convergence method applying a simple hemispheric equation if an aliasing velocity is used that results in a radial distance of at least 1.0 cm.
应用简单半球形方程通过近端血流会聚法准确测量反流容积所需的检查条件仍不确定。本研究调查了采用连续波和彩色多普勒近端血流会聚联合方法测量反流搏出量的要求。通过驱动5种反流搏出量（范围为30至70 ml/搏）通过横截面积范围为0.10至1.0 cm²的平面孔口产生25种脉动流率。检查了4种不同形状但孔口面积相同（0.5 cm²）的孔口（圆形、长轴/短轴比为2:1的矩形、长轴/短轴比为8:1的狭缝状和正方形）。根据先前描述的方程RV = 2π×(r max)²×AV×(TVI/Vmax)，通过连续波和彩色多普勒联合方法估计反流容积（RV），其中r max是最大径向距离，AV是混叠速度，TVI是反流束的时间速度积分，Vmax是反流束的峰值速度。绘制从圆形到矩形孔口的每种流率下实际和计算的RV之间的差异与近端会聚壳的径向距离的关系曲线，得到符合曲线函数的曲线，该曲线在1.0 cm处与零差异点相交。然而，在狭缝状孔口中，需要更远的距离（1.6 cm）才能达到最佳一致性。如果使用导致径向距离至少为1.0 cm的混叠速度，则应用简单半球形方程的连续波多普勒和近端血流会聚联合方法可以很好地估计实际反流搏出量。
