二维斑点追踪技术联合实时三维超声心动图评价下壁、后壁心肌梗死患者左心室收缩功能及同步性

目的: 联合应用二维斑点追踪技术(two-dimensional speckle tracking imaging, 2DSTI)与实时三维超声心动图(real time three dimensional echocardiography, RT 3DE)评价下壁、后壁心肌梗死患者左心室收缩功能与同步性。方法: 对20例下壁、后壁心肌梗死患者（心肌梗死组）及健康对照组20例行常规超声心动图检查，获得左心室舒张末期内径（LVEDD）、左心室收缩末期内径（LVESD）、左心室射血分数（LVEF）；同时存储心尖四腔心观、二腔心观、左室长轴观及二尖瓣水平、乳头肌水平、心尖水平左室短轴观的足够帧频二维图像。采用Qlab 9.0软件分析收缩期峰值纵向应变及圆周应变。采用RT 3DE获取左心室全容积图像，用Qlab 9.0软件获得左心室舒张末期容积(LVEDV)、左心室收缩末期容积(LVESV)、每搏输出量（SV）及射血分数(EF3d)，并分析左心室16节段达收缩期最小容积点时间的标准差(Tmsv16-SD)及最大时间差(Tmsv16 Dif)，并对标准差及时间差进行心率校正。结果： 两种方法测得的LVEF值心肌梗死组明显小于健康对照组(P<0.05)，LVEDD、LVESD、LVESV明显大于健康对照组(P<0.05)，SV明显小于健康对照组(P<0.05)；心肌梗死组下壁、后壁对应节段及相邻的部分节段纵向应变及圆周应变均比健康对照组明显降低（P<0.05）；心肌梗死患者Tmsv16-SD校正值和Tmsv16 Dif校正值均明显大于健康对照组（P<0.01）。结论： 2DSTI和RT 3DE能更加准确无创地判断下壁、后壁心肌梗死患者的节段性室壁运动异常及不同步性。

Evaluation of left ventricular systolic function and synchrony in patients with inferior and posterior myocardial infarction using two-dimensional speckle tracking imaging and real-time three-dimensional echocardiography

Objective Two-dimensional speckle tracking imaging(2DSTI) and real time three dimensional echocardiography(RT 3DE) were used to evaluate the left ventricular systolic function and synchrony in patients with inferior and posterior myocardial infarction. MethodsA total of 20 patients with inferior and posterior myocardial infarction (MI) and 20 healthy controls were enrolled in this study. Echocardiography was performed to collect the left ventricular end diastolic internal diameter (LVEDD), left ventricular end-systolic internal diameter (LVESD), ejection fraction (EF). We also collected the imagine clips of two cavity, four cavity, long axis at apex. In addition, we collected the imagine clips of short axis at mitral valve, papillary muscle and apex levels. Peak systolic longitudinal strain (L. Strain) and peak systolic circumferential strain (C. Strain) were analyzed by Qlab 9.0 software. We used RT 3DE to obtain the left ventricular full-volume images and used Qlab 9.0 software to analyze data, such as the end diastolic volume (LVEDV), end systolic volume (LVESV), stroke volume (SV) and ejection fraction (EF) of left ventricular, we also calculated the time to minimal systolic volume (Tmsv) of 16 segments and the maximal difference of corresponding segments (Tmsv16 Dif). The above parameters as a percentage of the cardiac cycle with different heart rates between patients were also calculated from the Qlab 9.0 software, which were Tmsv16-SD /R R(%)，Tmsv16 Dif /R R(%). ResultsThe LVEF detected by two ways in the MI group was significantly lower (P<0.05). The LVEDD, LVESD and LVESV were significantly higher and SV was significantly lower than those of the control (P<0.05). Both L. Strain and C. Strain of the inferior and posterior segments and part of adjacent segments in MI group were significantly lower than those in the control (P<0.05). The Tmsv16-SD/R-R(%) and Tmsv16-Dif/R-R(%) in MI group were significantly higher than the control (P<0.01). Conclusion2DSTI and RT-3DE may be used to more accurately and noninvasively evaluate the segmental motion abnormalities of left ventricular and dyssynchrony in patients with inferior and posterior myocardial infarction.