三维斑点追踪技术评价正常儿童左心室心肌纵向应变的研究

Evaluation of left ventricular systolic longitudinal strain in healthy children with three-dimensional speckle tracking

目的:应用三维斑点追踪技术(3DT)探讨正常儿童左心室心肌纵向应变特征及其与年龄的关系。方法:将126例3天～15岁健康受试者按年龄分为5组:A婴幼儿组(3天～3岁),B学龄前期组(3～5岁),C学龄期组(6～9岁),D青春前期组(10～12岁),E青春期组(13～15岁)。经胸超声同时采集左心室心尖四腔和两腔切面图像后,获取左心室三维全容积动态图像,存储图像后运用3DT分析软件进行在线分析。分析获取的左心室心肌整体及16节段收缩期纵向峰值应变(LS)测值。结果:①各组内比较:心尖段LS测值大于基底段及中间段,基底段至心尖段应变值递增,但差异无统计学意义(P>0.05)。②各组间比较:5组左室壁心肌整体及16节段LS测值随年龄增长大致呈递减趋势。5组各节段LS测值:除前间隔基底段及中间段、侧壁心尖段外,余节段差异均有统计学意义(P<0.05)。5组整体LS测值差异有统计学意义,其中A组、B组及C组整体LS测值大于D组及E组,差异有统计学意义(P<0.05)。结论:在出生后至青春期随着心脏的发育,左心室整体及16节段室壁心肌纵向应变值随年龄增加有一定的规律。

Objective： This study was performed to evaluate the characteristics of left ventricular systolic longitudinal strain（LS） in healthy children and its relationship with age using three-dimensional speckle tracking（3DT）.Methods： One hundred and twenty-six healthy subjects aged from 3 days to 15 years were divided into 5 groups： group A infants（3 days～3 years old）,group B pre school age children（3～5 years old）,group C school age children（6～9 years old）,group D preadolescent（10～12 years old） and group E adolescent age（13～15 years old）.The dynamic images of apical two and four-chamber views were displayed and apical full-volume acquisition was obtained in 126 subjects to visualize the entire left ventricular in a volumetric image.The full-volume images were recorded and then were analyzed by on-line 3DT analysis software.The longitudinal peak systolic strains of left ventricular by using 3DT were compared.Results： ①The LS of apical segment was larger than that of the basal segment and the middle segment,and it had a decreasing trend from the apical segment to the basal segment.But the difference was not statistically significant.②The LS value of the five groups showed a decreasing trend with age,and significant difference was found except for the two segments of anterior septum and apical segment of lateral wall.The global LS value of group A,B and C was larger than that in group D and E.And this difference was statistically significant.Conclusion： The global and 16 segments LS of left ventricular wall has a certain pattern in increasing with age after birth to adolescence with the development of the heart.