正常早期新生儿组织多普勒成像心肌活动指数分析

Tei index assessed by tissue Doppler imaging in normal early newborns

目的:采用组织多普勒成像测量正常早期新生儿的左、右心室心肌活动指数(Tei指数),观察时龄、体重、心率及前负荷等因素对Tei指数的影响,并建立早期新生儿Tei指数的正常值范围。方法:筛选出足月分娩的正常早期新生儿91例,应用组织多普勒成像技术检测其左、右房室瓣环的运动频谱,测量等容收缩时间(isovolumic contraction time,ICT)、等容舒张时间(isovolumic relaxation time,IRT)、射血时间(ejection time,ET),计算Tei指数。结果 :正常早期新生儿左、右心室Tei指数分别为0.38±0.04、0.32±0.06,两者间差异有统计学意义(P<0.05),且左、右心室Tei指数不受时龄、体重、心率、前负荷等因素影响。结论:组织多普勒成像测量Tei指数是一种简单、可靠、无创的定量综合评价心脏收缩和舒张功能的方法。确立正常早期新生儿的Tei指数范围,可为未来研究各种病理状态下早期新生儿心功能异常提供可靠的常规对照。

Objectives： To construct a reference chart for Tei index of normal early newborns assessed by tissue Doppler imaging（TDI） and to analyze the influencing factors such as age, weight, heart rate and preload on Tei index.Methods： Ninety-one normal early newborns were enrolled. The motion spectrum of mitral and tricuspid annulus was observed using TDI on early newborns. The isovolumic contraction time（ICT）, isovolumic relaxation time（IRT） and ejection time（ET） of the left ventricle（LV） and right ventricle（RV） were measured respectively and the Tei index was calculated using the formula（ICT＋IRT）/ET. Results： The Tei index of LV and RV in early newborn was significantly different（0.38±0.04 vs 0.32±0.06, P〈0.05）. The Tei index was not affected by factors such as age, weight, heart rate and preload. Conclusions：Tissue Doppler imaging provides an easily obtainable, noninvasive and reproducible method to assess Tei index for quanti-tative evaluating the cardiac systolic and diastolic function. The reference chart for Tei index of the early newborns provides a reliable conventional reference for future research on neonatal cardiac function in various pathological cardiac anomalies.