Abstract：
Rotational mechanics is a fundamental determinant of left ventricular ejection fraction (LVEF). The coding system currently employed in clinical practice does not distinguish between rotational patterns. We propose an alternative coding system that makes possible to identify the rotational pattern of the LV and relate it to myocardial function. Echocardiographic images were used to generate speckle tracking-derived transmural global longitudinal strain (tGLS) and rotational parameters. The existence of twist (basal and apical rotations in opposite directions) is expressed as a rotational gradient with a positive value that is the sum of the basal and apical rotation angles. Conversely, when there is rigid rotation (basal and apical rotations in the same direction) the resulting gradient is assigned a negative value that is the subtraction between the two rotation angles. The rotational patterns were evaluated in 87 healthy subjects and 248 patients with LV hypertrophy (LVH) and contrasted with their myocardial function. Our approach allowed us to distinguish between the different rotational patterns. Twist pattern was present in healthy controls and 104 patients with LVH and normal myocardial function (tGLS ≥ 17%, both). Among 144 patients with LVH and myocardial dysfunction (tGLS < 17%), twist was detected in 83.3% and rigid rotation in 16.7%. LVEF was < 50% in 34.7%, and all patients with rigid rotation had a LVEF < 50%. The gradient rotational values showed a close relationship with LVEF (r = 0.73; p < 0.001). The proposed coding system allows us to identify the rotational patterns of the LV and to relate their values with LVEF.
摘要：
旋转力学是左心室射血分数（LVEF）的基本决定因素。目前在临床实践中采用的编码系统不能区分旋转模式。我们提出了一种替代的编码系统，可以识别LV的旋转模式并将其与心肌功能相关联。超声心动图图像用于生成斑点追踪衍生的透壁整体纵向应变（tGLS）和旋转参数。扭曲的存在（相反方向的基底和根尖旋转）表示为具有正值的旋转梯度，该正值是基底和根尖旋转角度之和。相反，当存在刚性旋转(沿相同方向的基底和顶端旋转)时,所得到的梯度被分配为负值,即两个旋转角度之间的减法。在87名健康受试者和248名LV肥大（LVH）患者中评估了旋转模式，并与他们的心肌功能进行了对比。我们的方法使我们能够区分不同的旋转模式。扭曲模式存在于健康对照组和104例LVH和正常心肌功能患者(tGLS≥17%，both).在144例LVH和心肌功能障碍患者中（tGLS<17％），扭曲检测到83.3%，刚性旋转检测到16.7%。LVEF<50%，为34.7%，所有刚性旋转患者的LVEF<50％。梯度旋转值显示与LVEF密切相关(r=0.73;p<0.001)。所提出的编码系统允许我们识别LV的旋转模式并将它们的值与LVEF相关联。
