Ohara Yoshikazu, Fukuoka Yohko, Tabuchi Isao, Sahara Shinji, Hosogi Shingo, Nishimoto Mika, Yamamoto Katsuhito
Division of Cardiology, Kochi Health Sciences Center, Kochi, Japan.
Echocardiography. 2012 Nov;29(10):1172-80. doi: 10.1111/j.1540-8175.2012.01783.x. Epub 2012 Sep 11.
Myocardial function is heterogeneous in different myocardial layers. Recently, two-dimensional speckle tracking echocardiography has been used to define myocardial deformation parameters of the left ventricular (LV) segment. This study aimed to investigate strain in subendocardial and subepicardial layers in patients with aortic stenosis (AS) and preserved LV ejection fraction (LVEF) using speckle tracking echocardiography.
Parasternal short-axis and apical long-axis views of the left ventricle were acquired at the mid-papillary level in 35 control subjects and 32 patients with AS and preserved LVEF. Radial, circumferential, and longitudinal strain in subendocardial and subepicardial layers at the posterior and anteroseptal segments were calculated.
There was no significant difference in circumferential strain in subendocardial and subepicardial layers between the control subjects and the patients with AS. Similarly, there was no significant difference in epicardial radial strain at the posterior and anteroseptal segments between the control subjects and the patients with AS. Longitudinal strain at both the posterior and anteroseptal segments was significantly decreased in the AS group compared with that in the control group. AS patients had significantly decreased values of endocardial radial strain compared with those in controls (anteroseptal: 18.2 ± 11.2 vs. 34.5 ± 14.8, P < 0.005; posterior: 25.2 ± 14.8 vs. 32.6 ± 12.6, P < 0.05). In the AS group, endocardial radial strain in the posterior and anteroseptal segments was significantly correlated with the aortic valve area (posterior: r = 0.41, P < 0.05; anteroseptal: r = 0.33, P < 0.05).
Patients with AS and preserved LVEF have impaired longitudinal strain and endocardial radial strain, although circumferential strain and epicardial radial strain are preserved. Despite preserved LVEF, endocardial radial strain was associated with AS severity.
心肌功能在不同心肌层中是异质性的。最近,二维斑点追踪超声心动图已被用于定义左心室(LV)节段的心肌形变参数。本研究旨在使用斑点追踪超声心动图研究主动脉瓣狭窄(AS)且左心室射血分数(LVEF)保留的患者的心内膜下和心外膜下层的应变。
在35名对照受试者和32名AS且LVEF保留的患者的乳头肌中部水平获取左心室的胸骨旁短轴和心尖长轴视图。计算后段和前间隔段的心内膜下和心外膜下层的径向、圆周和纵向应变。
对照受试者和AS患者的心内膜下和心外膜下层的圆周应变无显著差异。同样,对照受试者和AS患者在后段和前间隔段的心外膜径向应变也无显著差异。与对照组相比,AS组在后段和前间隔段的纵向应变均显著降低。与对照组相比,AS患者的心内膜径向应变值显著降低(前间隔:18.2±11.2对34.5±14.8,P<0.005;后段:25.2±14.8对32.6±12.6,P<0.05)。在AS组中,后段和前间隔段的心内膜径向应变与主动脉瓣面积显著相关(后段:r = 0.41,P<0.05;前间隔:r = 0.33,P<0.05)。
AS且LVEF保留的患者的纵向应变和心内膜径向应变受损,尽管圆周应变和心外膜径向应变得以保留。尽管LVEF保留,但心内膜径向应变与AS严重程度相关。