Kim Hyung-Kwan, Sohn Dae-Won, Lee Sang-Eun, Choi Su-Yeon, Park Jin-Shik, Kim Yong-Jin, Oh Byung-Hee, Park Young-Bae, Choi Yun-Shik
Division of Cardiology, Department of Internal Medicine, Seoul National University College of Medicine, Cardiovascular Center, Seoul National University Hospital, Seoul, Korea.
J Am Soc Echocardiogr. 2007 Jan;20(1):45-53. doi: 10.1016/j.echo.2006.07.007.
Speckle tracking echocardiography (STE) has a unique feature of angle independence and, thus, may provide a powerful means of assessing left ventricular (LV) torsion (LVtor). The aims of this study were to assess: (1) the feasibility of 2-dimensional STE in the measurement of LVtor; and (2) the relationship of LVtor with age and conventional echocardiographic parameters.
We consecutively recruited 160 healthy volunteers. After obtaining conventional echocardiographic parameters, apical and basal short-axis rotations were assessed with STE. LVtor was defined as the net difference between rotation angles in the two short-axis planes normalized for LV longitudinal length.
Reliable LVtor measurement was possible only in 56 volunteers (35%). This low feasibility was largely a result of the failure to obtain reliable basal rotation values. In 56 volunteers who were finally enrolled in this study, a significant correlation was found between LV ejection fraction and LVtor (r = 0.56, P < .001) and this correlation was attributed to apical (r = 0.47, P < .001) but not basal (P = .14) rotation. There was no significant change in LVtor with aging. However, initial counterclockwise motion (r = -0.51, P = .001) and its interval (r = -0.44, P = .001) in the basal rotation gradually decreased with aging, and correlated with early transmitral inflow velocity (r = 0.44 and 0.49, respectively) and its deceleration time (r = -0.43 and -0.48, respectively) (all P < .001). In contrast, such correlations were not found for initial clockwise motion and its interval in the apical rotation.
Currently, STE has limited feasibility in the measurement of LVtor. There was no significant age-related change in LVtor. In LV rotations, basal rotation was affected by the age-related changes in the LV early diastolic filling, whereas apical rotation was mainly related to LV systolic performance.
斑点追踪超声心动图（STE）具有角度独立性这一独特特征，因此可能提供一种评估左心室（LV）扭转（LVtor）的有力方法。本研究的目的是评估：（1）二维STE测量LVtor的可行性；（2）LVtor与年龄及传统超声心动图参数的关系。
我们连续招募了160名健康志愿者。在获得传统超声心动图参数后，用STE评估心尖和心底短轴旋转。LVtor定义为两个短轴平面旋转角度的净差值，并根据LV纵向长度进行标准化。
仅在56名志愿者（35%）中能够可靠地测量LVtor。这种低可行性主要是由于未能获得可靠的心底旋转值。在最终纳入本研究的56名志愿者中，发现LV射血分数与LVtor之间存在显著相关性（r = 0.56，P <.001），这种相关性归因于心尖旋转（r = 0.47，P <.001）而非心底旋转（P =.14）。LVtor随年龄增长无显著变化。然而，心底旋转的初始逆时针运动（r = -0.51，P =.001）及其间期（r = -0.44，P =.001）随年龄增长逐渐减少，并与早期二尖瓣流入速度（分别为r = 0.44和0.49）及其减速时间（分别为r = -0.43和-0.48）相关（均P <.001）。相比之下，在心尖旋转的初始顺时针运动及其间期未发现此类相关性。
目前，STE测量LVtor的可行性有限。LVtor无与年龄相关的显著变化。在LV旋转中，心底旋转受LV舒张早期充盈与年龄相关变化的影响，而心尖旋转主要与LV收缩功能相关。
