分层应变技术分析重度中心性肥胖儿童左心室收缩功能改变

Analysis of Left Ventricular Systolic Function by Layer-Specific Strain in Severe Abdominal Obese Children With Normal Ejection Fraction

目的 应用分层应变技术分析重度中心性肥胖儿童左心室心肌各层应变的变化。资料与方法 前瞻性选取2018年7月—2019年7月在河南省儿童医院内分泌遗传代谢科就诊的7~14岁儿童,根据体重指数分为肥胖组53名和对照组55名,应用超声和分层应变技术,比较左心室各层心肌的纵向应变及圆周应变参数。结果 肥胖组与对照组左心室射血分数差异无统计学意义(t=0.28,P>0.05)。与对照组比较,肥胖组整体各层心肌纵向应变较低[内层:(-21.53±2.75)%比(-24.06±3.34)%;中层:(-18.18±3.08)%比(-21.38±2.35)%;外层:(-16.72±2.13)%比(-18.45±2.28)%],差异有统计学意义(t=4.13、5.75、6.29,P均<0.05)。肥胖组内层圆周应变低于对照组[(-27.10±4.41)%比(-30.20±4.76)%;t=3.47,P<0.05];中层、外层心肌圆周应变与对照组比较,差异无统计学意义(t=0.72、0.83,P均>0.05)。结论 左心室射血分数正常的重度中心性肥胖儿童已出现内、中、外层心肌纵向应变及内层圆周应变减低,左心室分层应变技术可用于发现其早期左心室心肌收缩功能改变。

Purpose To analyze the changes of left ventricular strain in severe abdominal obese children using layer-specific strain, and to quantitatively evaluate the usefulness of layer-specific strain as an estimation to identify early left ventricular systolic function. Materials and Methods A total of 53 obese children(obese group) aged 7-14 years old and 55 healthy children(control group) in the Department of Endocrinology and Inherited Metabolic Disease of Henan Children’s Hospital from July 2018 to July 2019 were collected according to body mass index. Longitudinal strain(LS) and circumferential strain(CS) of three-layer myocardium were assessed using layer-specific speckle tracking imaging. Results There was no significant difference in left ventricular ejection fraction among the obese group and control group(t=0.28, P>0.05). It showed a gradient decrease from the endocardium to the epicardium in both obese and control group. LS of three-layer myocardium [LSendo:(-21.53±2.75)% vs.(-24.06±3.34)%;LSmid:(-18.18±3.08)% vs.(-21.38±2.35)%;LSepi:(-16.72±2.13)% vs.(-18.45±2.28)%] in obese group were significantly reduced compare with those in control group(t=4.13, 5.75, 6.29, all P<0.05). The CS of endocardium was significantly lower in the obese group than in the control group [(-27.10±4.41)% vs.(-30.20±4.76)%;t=3.47, P<0.05].Compared with the control group, there was no significant difference in CS of middle myocardium and epicardium myocardium in obese group(t=0.72 and 0.83, all P<0.05). Conclusion Layer-specific strain can evaluate the CS of endocardium, LS of three-layer myocardium to sensitively identify early left ventricular systolic dysfunction in severe abdominal obese children with normal left ventricular ejection fraction.