速度向量成像技术对早期新生儿左室短轴运动变化的临床研究

目的 探讨速度向量成像技术（VVI ）评价早期新生儿左室短轴运动变化的应用价值.方法 足月新生儿32例,分别在出生后第24 h、48 h、72 h及96 h应用VVI技术动态监测每例新生儿的左室短轴收缩运动,包括左室短轴18个节段的收缩期峰值径向运动速度（SRVmax）、峰值径向应变（SRSmax）及峰值圆周应变（SCSmax）.结果 各组收缩期左室短轴方向的SRVmax在二尖瓣环水平、乳头肌水平及心尖水平呈现减小趋势,24 h组与96 h组各节段比较差异有统计学意义,24 h组与72 h组各节段比较呈增大趋势,96 h组与48 h组比较差异有统计学意义（P 〈 0.05）.SRSmax在同一水平各节段间差异无统计学意义,乳头肌水平显著高于心尖水平（P 〈 0.05）.SCSmax在同一水平各节段间差异无统计学意义,心尖水平高于二尖瓣环水平（P 〈 0.05）.结论 VVI技术能发现早期新生儿左室短轴运动的细微变化,在新生儿左室短轴收缩功能判定中具有较好的临床应用价值.

Evaluation of early neonatal left ventricular short-axis motion by velocity vector imaging

Objective To assess the application value of velocity vector imaging （VVI）in evaluating left ventricular short-axis motion in early neonate. Methods Thirty-two full-term newborns were divided into four groups according to age in this study（ 24 h, 48 h, 72 h and 96 h）. The short-axis contraction motion of left ventricle was dynamically monitored by VVI, the systolic peak velocity （SRVmax）, systolic peak radial strain（SRSmax ） and the systolic peak circumferential strain（SCSmax） of 18 segments were measured. Results The SRVmax in each group showed decreasing trend from the mitral annulus level, papillary muscle level to apical level, there was significant difference of each segment between 24 h group and 96 h group, 96 h group and 48 h group （P 〈 0.05）,it showed increasing trend in the segments of 24 h group and 72 h group. There was no significant difference of SRSmax in each segment of all groups, while the SRSmax in papillary muscle level was significantly higher than that of apical level （P 〈 0.05 ）. There was no significant difference of SCSmax in each segment of all groups, while the SCSmax inlevel of apex was higher than that of the mitral annulus （P 〈 0.05 ）. Conclusion VVI can early detect neonatal small changes in left ventricular short-axis movement, it is a potientially useful tool for evaluating the systolic function of left ventricle in neonate.