超声二维斑点追踪技术评价健康婴幼儿、儿童及青少年左室扭转及解旋运动的研究

Assessment of Left Ventricular Torsion and Untwisting in healthy infants,children and adolescents by Two-Dimensional Ultrasound Speckle Tracking Imaging

目的运用超声斑点追踪技术（STI）评价正常婴幼儿、儿童及青少年左心室扭转及解旋运动特征。方法选取205例3天~15岁正常健康人,按年龄分为5组：婴幼儿组（3天~2岁）,学龄前期组（3~5岁）,学龄期组（6~9岁）,青春前期组（10~12岁）,青春期组（13~15岁）。取胸骨旁左室心尖和心底短轴切面对左室扭转进行测量。计算出收缩期扭转角度峰值（Ptw）、标化收缩期扭转角度（PtwN）、收缩期扭转速度峰值（PTV）、解旋速度峰值（PUV）,比较不同年龄组的差别。观察左室扭转与性别、身高、体重、心率、射血分数等的相关关系。结果①左室扭转运动主要表现收缩期为逆时针方向扭转,舒张期为顺时针方向扭转。②随着年龄的增加,Ptw、PTV、PUV测值在各组间逐渐增加,各组间指标差异均有统计学意义（P〈0.01）;PtwN随着年龄的增加逐渐降低（P〈0.01）。③全部观察者左室扭转角度与左室舒张末期内径及左室后壁舒张期厚度相关（P〈0.01）,与性别、身高、体重、心率、射血分数等均不相关。结论应用超声二维斑点追踪显像技术可无创性评价健康婴幼儿、儿童及青少年左室扭转运动特征。临床在应用扭转评价左室功能时,应充分考虑年龄因素的影响。

Objective To analyze left Ventricular Torsion and Untwisting in healthy infants and adolescents by Two-Dimensional Ultrasound Speckle Tracking Imaging.Methods 205 healthy volunteers,aged from 3 days to 15 years,were divided into 5 groups： Group Infancy（3 days-2years）,Group Pre-school age（3-5years）,Group School age（6-9years）,Group Preadolescence（10-12years）,and Group Adolescent age（13-15years）.Basal and apical short axis images of left ventricle were acquired to analysis LV rotation（LVtor） and LVtor velocity.Peak twist（Ptw）;peak twisting velocity（PTV）,peak untwisting velocity（PUV）,were measured separately and the values of the above parameters was compared between different groups.Results ① The LVtor velocity showed a systolic counterclockwise twist followed by a diastolic clockwise twist at the apex in infants、children and adolescents;② LV torsion,PTV、PUV increased with age.Although LV torsion overall showed age-related increases,when normalized by LV length,it showed higher values in infancy.The proportion of untwisting during isovolumic relaxation was lowest in infancy,increased during childhood,and leveled off thereafter;③ LVtor were correlated with end-diastolic LV diameter and posterior wall thickness（P0.01）.And has no correlation with sex,height,weight,heart rate,LVEF.Conclusion LVtw can be measured noninvasively by 2-dimensional ultrasound speckle tracking imaging.The age-related changes of LVtw should be fully take into consideration when assessing LV function.