应用组织多普勒成像技术了解健康儿童左、右心室功能的变化特点

Development of left and right ventricular function in healthy children explored by tissue Doppler imaging

目的 应用组织多普勒成像技术了解健康儿童左、右心室功能随年龄增长的变化特点及相互关系.方法 收集2013年11月至2014年2月在中山大学附属第一医院参与检查研究的0 -15岁健康儿童,按年龄段分为6组,婴儿期组（0-1岁）、幼儿期组（＞1-3岁）、学龄前期组（＞3 -6岁）、学龄期组（＞6 -9岁）、青春前期组（＞9- 12岁）、青春期组（＞12 - 15岁）;并征集健康青少年（＞15-25岁）作为青少年组.每组收集15- 30例志愿者.研究对象均行超声心动图检查,包括心脏腔径测量;频谱多普勒测量舒张早期血流速度（E）/舒张晚期血流速度（A）比值;组织多普勒测量房室瓣环处组织运动速度与时间参数,收缩期组织运动速度（s）、舒张早期组织运动速度（e）及舒张晚期组织运动速度（a）、等容收缩期、射血期、等容舒张期,计算等容收缩期加速度（ⅣA）与Tei指数.比较各组间所得数据,探讨与年龄增长的关系及相关因素,并进一步比较左、右心室功能指标关系.结果 左心室Tei指数与等容收缩期在青春期显著减低;血流E/A比值与e/a比值自婴儿期至学龄前期随年龄增长逐渐增大,之后各年龄组间差异无统计学意义（P＞0.05）.右心室Tei指数、ⅣA、E/A、e/a各年龄组间差异无统计学意义（P＞0.05）.左心室s、ⅣA显著小于右心室（P均＜0.001）,而E/e、e/a显著高于右心室（P均＜0.001）.结论 健康儿童左心室收缩功能在青春期增强,舒张功能自婴儿期至学龄前期逐渐增强,之后维持稳定.右心室收缩、舒张功能随年龄增长无明显变化.左心室舒张功能强于右心室,右心室纵向收缩功能强于左心室.

Objective To explore the development and interaction of left and right ventricular function in healthy children using tissue Doppler imaging.Methods Healthy children aged 0-15 years and adolescents were recruited,then children were divided into 6 groups：0-1 year,〉 1-3 years,〉 3-6 years,〉 6-9 years,〉 9-12 years,〉 12-15 years.Healthy adolescents aged 〉 15-25 years were also recruited.Every subject underwent echocardiography including cardiac dimension measurements,atrio-ventricular valvular velocity and early-diastolic flow velocity（E）/late-diastolic flow evlocity（A） ratio measured by pulsed color Doppler,atrio-ventricular annular myocardial velocity （including systolic velocity （s）,early diastolic velocity （e） and late diastolic velocity （a））,time intervals （including isovolumic contraction time,ejection time and isovolumic relaxation time）,isovolumic acceleration （ⅣA） and Tei index measured by tissue Doppler imaging.Results were compared among different groups,the correlations with age and other factors were explored.Furthermore,comparison was done between left and right ventricular functional parameters.Results Left ventricular Tei index and isovolumic contraction time were significantly lower during puberty.From infancy to pre-school stage,left ventricular E/A （flow velocity） and e/a（tissue velocity） increased accordingly,then presented with no significant changes among the following age groups（P 〉 0.05）.There were no significant differences in right ventricular Tei index,ⅣA,E/A （flow velocity） and e/a （tissue velocity） among the 6 groups （P 〉 0.05）.Left ventricular systolic myocardial velocity （s） and ⅣA were significantly lower than right ventricle （all P 〈 0.001）.However,left ventricular E/e（flow velocity） and e/a（tissue velocity） were significantly greater than right ventricle （all P 〈0.001）.Conclusions In healthy children,left ventricular systolic function enhances during puberty,diastolic function increases from infancy to pre-school stage,then keeps stable till adolescents.Right ventricular systolic and diastolic function present with no significant changes during growth.Left ventricular diastolic function is greater than right one,however,right ventricular longitudinal systolic function is greater than left one.