斑点追踪技术评价正常儿童左心室径向应变率

Speckle tracking echocardiography evaluation of regional left ventricular radial strain rate in healthy children

目的探讨0~18岁正常儿童左心室心肌局部收缩期径向峰值应变率（SrR）参考值,及其与年龄、心率的相关性。方法获取164名0~18岁正常儿童胸骨旁左心室短轴二维动态图像,采用GE Echo PAC软件分析并得到左心室SrR,比较各节段SrR值,对SrR与年龄、心率进行相关分析。结果二尖瓣水平前间隔基底段与下壁基底段SrR差异有统计学意义（P=0.002）;乳头肌水平前间隔中间段与侧壁中间段SrR差异有统计学意义（P=0.033）;心尖水平各节段差异均无统计学意义（P均〉0.05）。除前间隔心尖段、前壁心尖段以外,其余节段SrR与年龄均相关（R^2=0.014~0.206,P〈0.05）;左心室壁各节段SrR与心率均相关（R^2=0.048~0.237,P〈0.05）。二尖瓣水平各节段SrR与心率相关（R^2=0.066~0.123,P〈0.05）;乳头肌水平各节段SrR与年龄和心率相关（R2=0.088~0.268,P〈0.05）;心尖水平各节段SrR与心率相关（R^2=0.048~0.127,P〈0.05）。观察者内、观察者间的变异系数分别为4.2%、8.6%。结论运用斑点追踪技术评价正常儿童左心室局部心肌SrR时需考虑年龄、心率因素。

Objective To explore the reference values of regional peak systolic radial strain rate（SrR）in healthy children,and evaluate the correlation between SrR and age,heart rate.Methods Transthoracic left ventricular short-axis twodimensional echocardiographic images were obtained from 164 healthy children.All images were analyzed off-line in GE EchoPAC workstation and regional SrR were accessed,and the correlation was performed between SrR and age,heart rate.Results The SrR of basal anterior septum and inferior wall anterior septum in papillary level,middle segments and lateral wall of anterior septum at papillary muscle level had statistical difference（P=0.002,0.033）.There were no statistical difference of segments in apex level（all P〉0.05）.Except apex segments and anterior wall of anterior septum,SrR of other segments correlated with age（R^2=0.014—0.206,P〈0.05）.SrR of all left ventricular segments correlated with heart rate（R^2=0.048—0.237,P〈0.05）.SrR of all segments at papillary level correlated with heart rate（R^2=0.066—0.123,P〈0.05）.SrR of all segments at the papillary muscle level correlated with heart rate and age（R^2=0.088—0.268,P〈0.05）.SrR of all segments at the apex lever correlated with heart rate（R^2=0.048—0.127,P〈0.05）.Intra-observer variability and the inter-observer variability were 4.2%and 8.6%.Conclusion Age and heart rate effects must be considered when evaluating the SrR in children by speckle tracking echocardiography.