Hayashi H, Okajima M, Yamada K
Am Heart J. 1976 May;91(5):607-17. doi: 10.1016/s0002-8703(76)80146-9.
In 46 dogs with experimentally produced complete A-V block, the P and the Ta waves before and after the atrial injury were recorded in scalar orthogonal ECG leads at high speed and high amplification. The P and the Ta loops were drawn by hand from the scalar ECG'S. In the dogs without atrial injury, the maximum Ta vector was oriented to the right, superiorly and anteriorly. The P-T angle was close to 180 degrees in each of the three planes. The magnitude of the maximum Ta vector was nearly proportionate to that of the maximum P vector in each plane. The Ta loop was a smooth, elongated ellipse in configuration and showed clockwise rotation in all planes, as did the P loop. The spatial atrial gradient obtained from the scalar ECG was small. In the dogs with atrial injury, the Ta loop changed in direction, configuration, and inscription direction. The P-Ta angle and the relative magnitude of the maximum Ta vector to that of the maximum P vector changed markedly. The change of the P loop remained minimum. The maximum Ta vector and spatial atrial gradient were oriented toward the atrial injury site. The magnitude of the spatial atrial gradient was extremely large after injury. These findings were thought to be important in suggesting the presence of atrial injury and its localization.
在46只实验性造成完全性房室传导阻滞的犬中，在心房损伤前后，通过高速和高放大倍数，在标量正交心电图导联记录P波和Ta波。P环和Ta环由标量心电图手工绘制。在无心房损伤的犬中，最大Ta向量向右、上、前方。在三个平面中，P - T角均接近180度。在每个平面中，最大Ta向量的大小与最大P向量的大小几乎成比例。Ta环形态为光滑、细长的椭圆形，在所有平面均呈顺时针旋转，P环也是如此。从标量心电图获得的空间心房梯度较小。在有心房损伤的犬中，Ta环在方向、形态和记录方向上发生改变。P - Ta角以及最大Ta向量与最大P向量的相对大小显著变化。P环的变化保持最小。最大Ta向量和空间心房梯度指向心房损伤部位。损伤后空间心房梯度的大小极大。这些发现被认为对于提示心房损伤的存在及其定位很重要。
