应用Tei指数评价早产儿早期右心室功能的研究

目的探讨Tei指数在评价早产儿右室心功能中的作用及其影响因素,为临床评估及治疗提供依据。方法对早产儿和足月儿各50例进行心脏组织多普勒（tissue Dopplerimaging,TDI）检查,测定右室射血分数（RVEF）、肺动脉收缩压（PASP）、三尖瓣口舒张早期峰值（E峰）、舒张晚期峰值（A峰）,计算E/A值结果 ,同时记录右房室瓣环处的组织多普勒频谱图,测定等容收缩期时间（ICT）与等容舒张期时间（IRT）之和（ICT＋IRT）及射血期时间（ET）,公式（ICT＋IRT）/ET计算Tei指数。结果早产儿与足月儿RVEF值及E/A比值差异无统计学医院（P〉0.05）,早产儿右室Tei指数较足月儿明显升高（0.48±0.07VS0.38±0.05,P〈0.01）。新生儿右室Tei指数随孕周及出生体重增加逐渐下降（孕周r=-0.78,P〈0.01;体重r=-0.73,P〈0.01）,与心率、体表面积无明显相关性（P〉0.05）。结论右室Tei指数是评价早产儿右室心功能早期变化简便而敏感的多普勒超声新指标,优于传统超声指标。

Assessment of Early Right Ventricular Function in Preterm Infant by Tei Index

Objective To investigate the roles of the Tei index of right ventricle（RV-Tei） and influencing factors in assessing right ventricular function in preterm infants,in hopes of providing evidences for the clinical evaluation and treatment.Methods Echocardiographic examinations were performed on both 50 preterm and term infants,respectively.Right ventricular ejection fraction（RVEF）,pulmonary artery systolic pressure（PASP）,tricuspid early diastolic peak（peak E） and the late diastolic peak（peak A） were measured,and E/A ratio was acquired.The Tei index of right ventricle（RV-Tei）was measured by Doppler spectrum.The isovolumic relaxation time（IRT）,isovolumic contraction time（ICT） and ejection time（ET） was measured by Doppler spectrum and the Tei index was calculated using the formula（IRT＋ICT）/ET.Results Comparing the preterm infants groups with term infants groups,the RVEF and E/A ratio of right ventricle had no statistical difference（P0.05）.The RV-Tei in preterm infants groups was higher than the term infants groups（0.48±0.07 VS 0.38±0.05,P0.01）.The Tei index of the neonates RV decreased linearly with advancing gestational week and weight（gestational week：r=-0.78,P0.01;weight：r=-0.73,P0.01）,but had no correlation with their heart rate and body surface area（P0.05）.Conclusion RV-Tei index can indicate early overall changes of the right ventricular function and is better than conventional ultrasound technology in preterm infant.