超声三维斑点追踪技术评估主动脉瓣狭窄患者左室功能

Assessment on the left ventricular function in aortic stenosis patient using three-dimensional speckle-tracking echocardiography

目的探讨超声三维斑点追踪技术评估主动脉瓣狭窄患者左室功能的临床应用价值。方法纳入33例左室射血分数正常的中、重度主动脉瓣狭窄患者和57名正常对照者。按照狭窄程度分为中度狭窄亚组15例和重度狭窄亚组18例;应用三维斑点追踪技术获得左室总体长轴应变(GLS)、总体环向应变(GCS)、总体径向应变(GRS)、面积应变、三维应变、扭转(twist)、旋转(rotation)、扭矩(torsion);应变、位移指标十二节段(6个基底段和6个中间段)达到收缩期最小容积时间的标准差(Tmsvl2-SD)等参数。使用SPSS 17.0软件进行统计分析。结果主动脉瓣狭窄组患者GRS、GLS、三维应变较正常对照均降低(P=0.043、P<0.001、P=0.03),左室各节段扭转值均较对照组明显增大(基底段P=0.003,中间段P=0.011,心尖段P<0.001),心尖段旋转角度以及基底段和心尖段扭矩增加均有统计学意义(P<0.001、P=0.005、P<0.001)。症状亚组分析中,两组狭窄程度及各超声指标差异无统计学意义(P>0.05);狭窄程度亚组分析中,重度狭窄组环向应变率低于中度狭窄组(P=0.017),而GRS、GCS、GLS随着狭窄程度增加,均呈现出降低趋势。结论超声三维斑点追踪技术定量指标可较LVEF更早反映主动脉瓣狭窄患者左室扭转、旋转运动的变化;主动脉瓣狭窄程度与患者的心脏功能变化相关性更紧密。

Objective The aim of this study was to compare the left ventricle function in varying degrees AS using three-dimensional speckle-tracking echocardiography. Methods We prospectively enrolled 33 AS patients with aortic flow velocity 〉3.0m/s, mean valve pressure gradient 〉20mmHg, 57 controls were enrolled. Further AS patients were divided into different groups according to aortic stenosis gradient. AS gradient subgroup had 15 moderate AS patients （mean gradient〈40mmHg） and 18 severe AS patients （mean gradient≥40mmHg）. All patients underwent two-dimensional echocardiography and three-dimensional speckle-tracking eehocardiography. Results Aortic stenosis patients had lower three-dimensional GRS, GLS and three dimensional strain than control group than control group（P= 0. 043, P〈0. 001, P= 0. 03,respectively）. In stenosis group, left ventricular torsion of each segment significantly increased compared with the control group（basal segments P=0. 003, the middle section P=0. 011, apical segment P〈0. 001）; left ventricular apical rotation angle, basal and apical segment tortion increase, the difference was statistically significant （P〈0. 001, P=0. 005, P〈0. 001）. According to the degree of stenosis, circumferential strain rate in severe stenosis group is lower than the moderate stenosis group （P=0. 017）, while GRS, GCS, GLS increases with the degree of stenosis, showed a decreasing trend, but the difference was not statistically significant. Conclusion For the early assessment of left ventricu- lar dysfunction in patients with aortic stenosis, the radial strain and overall technical quantitative longitudinal strain may be more sensitive indicators of three-dimensional ultrasound speckle tracking. These indicators can early reflect changes of twist and rotation in aortic stenosis patients. The early heart function are changing with different degree of aortic stenosis.