超声斑点追踪技术对心肌梗死患者室壁运动的二维应变研究

目的 应用超声斑点追踪技术测量心肌梗死患者梗死节段室壁的二维应变，探讨其诊断局部室壁运动异常的临床应用价值。方法30例正常人及30例心肌梗死患者，分别记录左室短轴（二尖瓣，乳头肌，心尖部）图像和心尖位四腔切面，二腔切面，左室长轴高帧频图像，应用二维应变软件测量各个节段的二维应变值。结果心肌梗死患者梗死节段共177个，其中158个节段通过超声斑点追踪技术，获得二维应变值。基底段，中间段及心尖段纵向应变值与正常对照组均明显减低，有显著性差异，P〈0．01；左室短轴（二尖瓣，乳头肌及心尖部水平）的径向应变及圆周应变与正常对照组均明显减低，有显著性差异，P〈0．05；旋转角度无统计学差异。结论超声斑点追踪技术可准确评价节段性室壁运动异常，为临床评价心肌梗死患者左心收缩功能提供无创性新方法．

Two-dimensional strain in patients with myocardial infarction measured by speckle tracking echocardiography

Objective To evaluate the clinical value of speckle tracking echocardiography for the measurement of two-dimensional strain in patients with myocardial infarction.Methods Study population consisted of 30 patients with myocardial infarction and 30 healthy subjects.High frame rate two-dimensional images were recorded from the left ventricular short-axis views at the levels of mitral annulus,papillary muscle and apex,and the apical four-chamber view,two-chamber view and long-axis view of the left ventricle respectively.The longitudinal strain was measured in the apical views.Radial strain,circumferential strain and rotation were measured in the left ventricular short-axis views using 2D strain software.Results Two-dimensional strain was obtained in 158 of 177 segments with regional wall motion abnormalities in patients with myocardial infarction.Infarct segments in myocardial infarction patients showed significant reduction of longitudinal strain compared with normal myocardium(P<0.01).Infarct segments in myocardial infarction patients showed significant reduction of radial strain and circumferential strain compared with normal myocardium(P<0.05).There was no significant difference in myocardial rotation between normal myocardium and infarct segments.Conclusion Regional wall motion of left ventricule in patients with myocardial infarction can be evaluated accurately with Speckle tracking echocardiography.