Kihara Y, Osakada G, Fujisawa A, Hashimoto T, Tomioka N, Sasayama S, Kawai C
J Cardiogr. 1985 Jun;15(2):285-95.
To quantify left ventricular (LV) regional wall motion using two-dimensional echocardiography, reference points such as the center of left ventricular gravity or an intersecting point of radial grids were conventionally used, assuming that they were near or at the center of LV contractile motion. However, since the LV does not contract homogeneously, their positions might be quite different. Endocardial high density spots in two-dimensional echocardiograms were used as markers for LV regional wall motion, and we determined the center of LV contractile motion (C) at papillary muscle level in the parasternal short-axis view for 10 normal subjects (control group) and eight patients with aortic regurgitation (left ventricular volume overload; LVVO group). In one subject, each of six endocardial high density spots extracted from different LV regions, and were traced frame by frame throughout one cardiac cycle using a video motion analyzer, and their systolic movements were shown by six vectors. Using the method of least squares, the point of convergence of vectors (C) was determined from the point toward which the six vectors were directed. The LV centers of gravity at end-diastole (Ged) and at end-systole (Ges) were also determined by tracing the endocardial surface on video frames. The distributions of C, Ges, and Ged were compared. In the control group, point C was at the point 35% distant from Ged toward the middle of the interventricular septum (IVS). Ges deviated from Ged in the same direction as point C, but the distance was one third of C(11%). In the LVVO group, the distribution of Ges referred to Ged was similar to that of the control group, however, point C was closer to Ged, since its deviation was 16% of the radius. These results suggest that point C, which is determined by the directions of regional wall motion, reflects the contractile pattern of the whole LV. This might be termed the center of LV contraction. Using it as a reference, we were able to obtain more accurate quantitative data about LV regional wall motion.
为了使用二维超声心动图对左心室（LV）局部壁运动进行量化，传统上使用诸如左心室重心中心或径向网格交点等参考点，假定它们靠近或位于左心室收缩运动的中心。然而，由于左心室并非均匀收缩，它们的位置可能有很大差异。二维超声心动图中的心内膜高密度点被用作左心室局部壁运动的标记，我们在胸骨旁短轴视图的乳头肌水平确定了10名正常受试者（对照组）和8名主动脉瓣反流患者（左心室容量超负荷；LVVO组）的左心室收缩运动中心（C）。在一名受试者中，从左心室不同区域提取六个心内膜高密度点，使用视频运动分析仪在整个心动周期逐帧追踪它们，其收缩运动由六个向量表示。使用最小二乘法，从六个向量所指向的点确定向量的收敛点（C）。舒张末期（Ged）和收缩末期（Ges）的左心室重心也通过在视频帧上追踪心内膜表面来确定。比较了C、Ges和Ged的分布。在对照组中，点C位于距Ged朝着室间隔（IVS）中部35%的位置。Ges与点C的方向相同偏离Ged，但距离是C的三分之一（11%）。在LVVO组中，Ges相对于Ged的分布与对照组相似，然而，点C更靠近Ged，因为其偏差是半径的16%。这些结果表明，由局部壁运动方向确定的点C反映了整个左心室的收缩模式。这可能被称为左心室收缩中心。以它作为参考，我们能够获得关于左心室局部壁运动更准确的定量数据。
