Tumenbayar Maidar, Yamaguchi Kazuto, Yoshitomi Hiroyuki, Endo Akihiro, Tanabe Kazuaki
Division of Cardiology, Shimane University Faculty of Medicine, 89-1 Enya-cho, Izumo, Shimane, 693-8501, Japan.
J Echocardiogr. 2018 Mar;16(1):28-33. doi: 10.1007/s12574-017-0347-3. Epub 2017 Aug 11.
Two-dimensional (2D) speckle tracking imaging (STI) is a non-invasive method used to assess subtle changes in left ventricular (LV) function such as strain and rotational dynamics. However, 2D methodology is complicated by issues such as the out-of-plane problem inherent in short-axis imaging. In addition, circumferential rotation contributes to three-dimensional (3D) wall deformations and affects tracking accuracy. By using 3D-STI technique, we evaluated LV global longitudinal strain (GLS) and apical rotation in severe aortic stenosis (AS) patients with preserved LV ejection fraction (EF).
LV GLS and apical rotation were evaluated using 3D-STI in 20 severe AS patients (79 ± 8 years old; aortic valve area 0.7 ± 0.2 cm) with preserved LVEF (68 ± 7%). Data were compared with those of 11 hypertensive LV hypertrophy (LVH) patients (75 ± 10 years old, EF = 66 ± 4%) and 12 controls (healthy individuals: 30 ± 14 years old, EF = 63 ± 6%).
Compared with LVH patients, severe AS patients had significantly decreased values of GLS (-13.0 ± 2.4 vs. -10.4 ± 2.0%, p = 0.008). In contrast, LV rotation was significantly higher in AS than LVH patients (13.9 ± 3.0° vs. 10.8 ± 2.5°, p = 0.007). There was no significant difference in stroke volume index among three groups. In these three groups, severe AS patients had significantly decreased values of GLS [analysis of variance (ANOVA), p < 0.001] and increased LV rotation (ANOVA, p < 0.001).
In severe AS patients, impaired GLS existed although LVEF was preserved. However, LV rotation was increased in patients with severe AS probably to maintain the LV stroke volume.
二维（2D）斑点追踪成像（STI）是一种用于评估左心室（LV）功能细微变化（如应变和旋转动力学）的非侵入性方法。然而，二维方法因短轴成像中固有的平面外问题等而变得复杂。此外，圆周旋转会导致三维（3D）壁变形并影响追踪准确性。通过使用三维斑点追踪成像（3D-STI）技术，我们评估了左心室射血分数（EF）保留的重度主动脉瓣狭窄（AS）患者的左心室整体纵向应变（GLS）和心尖旋转。
使用3D-STI评估20例左心室射血分数保留（68±7%）的重度AS患者（79±8岁；主动脉瓣面积0.7±0.2cm²）的左心室GLS和心尖旋转。将数据与11例高血压左心室肥厚（LVH）患者（75±10岁，EF = 66±4%）和12例对照组（健康个体：30±14岁，EF = 63±6%）的数据进行比较。
与LVH患者相比，重度AS患者的GLS值显著降低（-13.0±2.4对-10.4±2.0%，p = 0.008）。相反，AS患者的左心室旋转显著高于LVH患者（13.9±3.0°对10.8±2.5°，p = 0.007）。三组之间的每搏输出量指数无显著差异。在这三组中，重度AS患者的GLS值显著降低[方差分析（ANOVA），p < 0.001]且左心室旋转增加（ANOVA，p < 0.001）。
在重度AS患者中，尽管左心室射血分数得以保留，但仍存在整体纵向应变受损的情况。然而，重度AS患者的左心室旋转增加可能是为了维持左心室每搏输出量。
