超声斑点追踪技术测量二尖瓣环位移评价左心室收缩功能的临床研究

目的 分析超声二维斑点追踪技术测定的二尖瓣环收缩期位移(MAD)与左室射血分数(LVEF)的相关性,探讨MAD评价左室收缩功能的可行性.方法 选择96例观察对象,其中健康对照组30例,患者66例.记录心尖四腔及二腔观二维图像并输入Qlab6.0工作站,自动获取二尖瓣环侧壁(MADlat)、后室间隔(MADsep)、前壁(MADant)、下壁(MADinf)四个位点的MAD以及心尖四腔观二尖瓣环连线中点(mid)处MAD,并计算MADmid与左室舒张末长径百分比(MADmid%).应用实时三维超声心动图方法获取LVEF.分析各MAD参数与LVEF之间的关系.结果 ①MADsep、MADlat、MADant、MADinf和MADmid之间差异无统计学意义.②各位点MAD均与LVEF值显著相关,MADmid和MADmid%与LVEF的相关系数分别为0.87和0.89(P<0.01).③MADmid评价LVEF>50%的截断点值为8.9 mm,敏感性为95%,特异性为80%;MADmid%评价LVEF>50%的截断点值为10.9%,敏感性为95%,特异性为85%.结论 应用超声二维斑点追踪技术测定的二尖瓣环MAD与LVEF存在良好的相关性,有望成为评价左室收缩功能的新方法.

Evaluation of left ventricular systolic function by measuring the mitral annular displacement with speckle tracking imaging

Objective To explore the value of peak systolic displacement of mitral annulus in evaluating left ventricular systolic function by speckle tracking imaging(STI).Methods The study population consisted of 96 subjects. The apical four-chamber view and two-chamber view were obtained and the systolic displacements of mitral annulus were measured at lateral, spetum, anterior and inferior mitral annulus (MADlat, MADsep, MADant, MADinf).The systolic displacements of mitral annulus midpoint (MADmid) and its ratio to the length of left ventricle at end-diastole(MADmid%) were calculated.Left ventricular ejection fraction(LVEF) was measured by three-dimensional echocardiography.The correlation of these displacements parameter with LVEF was analyzed.Results ① There was no significant difference among MADsep, MADlat, MADant, MADinf and MADmid(P>0.05).②There was significant correlation between LVEF and these parameters (P <0.01) ,and MADmid and MADmid% showed an excellent correlation with LVEF (r = 0.87 and 0.89 respectively, P<0.01).③The cut-off value of MADmid for LVEF>50% was 8.9 mm with a sensitivity of 95% and a specificity of 80% while the cut off value of MADmid% for LVEF>50% was 10.9% with a sensitivity of 95% and a specificity of 85%.Conclusions Displacement of mitral annulus by STI showed an excellent correlation with LVEF, and it may be a new promising method for routine evaluation of left ventricular systolic function with its high feasibility, simplicity and accuracy.