Nakaya Y, Suma Y, Takahashi M, Saito K, Sumi M, Murakami M, Fujino K, Mori H
J Electrocardiol. 1984 Apr;17(2):161-8. doi: 10.1016/s0022-0736(84)81091-2.
The U loops of vectorcardiograms (VCG) were recorded in 100 normal subjects and 123 subjects with hypertension, using a direct-writing vectorcardiograph with memory function. These U loops were examined qualitatively and quantitatively. Subjects with hypertension were classified into four groups on the basis of electrocardiographic findings, and the correlation between findings on the U loop and the severity of hypertension was studied. The U loop of normal subjects was directed similarly to the T loop, showing either an arc or semilunar shape in the horizontal plane. In hypertensive subjects the U loop tended to be displaced anteroinferiorly and to the right with an increase in severity of hypertension. In these subjects the U loop was of slightly greater amplitude than in normal subjects, and was long and slender in shape. Anterior and rightward displacement of the U loop was also observed in hypertensive cases who showed no abnormality in the T wave of standard lead ECGs or in the T loop of the VCG. These findings seem useful as clinical parameters of the hemodynamic state in the early stage of hypertension. Based on these results, it was hypothesized that mechanical factors, such as stretch of the ventricular muscles induced by pressure loading of the left ventricle, may contribute greatly to genesis of the U loop.
使用具有记忆功能的直描式心电向量图仪，记录了100名正常受试者和123名高血压患者的心电向量图U环。对这些U环进行了定性和定量检查。根据心电图表现将高血压患者分为四组，并研究了U环表现与高血压严重程度之间的相关性。正常受试者的U环方向与T环相似，在水平面呈弧形或半月形。在高血压患者中，随着高血压严重程度的增加，U环往往向前下和向右移位。在这些患者中，U环的幅度略大于正常受试者，形状细长。在标准导联心电图T波或心电向量图T环无异常的高血压病例中，也观察到U环向前和向右移位。这些发现似乎可作为高血压早期血流动力学状态的临床参数。基于这些结果，推测机械因素，如左心室压力负荷引起的心室肌拉伸，可能在很大程度上促成U环的形成。
