应用多普勒超声在妊娠11^(+0)～14^(+6)周筛查先天性心脏畸形的初步研究

Primary study of doppler ultrasound in screening the congenital cardiac defects between 11^(+0) and 14^(+6) weeks′ gestation

目的在妊娠早期末和妊娠中期初联合应用二维超声和多普勒超声观察胎儿心脏结构、心内和心外血流,探索在此阶段多普勒超声在筛查胎儿先天性心脏发育异常中的价值。方法在妊娠11+0～14+6周进行常规胎儿产前超声检查,结合颈项透明层厚度(NT)和颈部软组织厚度(NF)测量,观察胎儿心脏大体结构,应用脉冲多普勒超声获取胎儿二尖瓣、三尖瓣和静脉导管血流频谱,并进行相应的血流频谱分析。所有胎儿在妊娠中期进行胎儿超声心动图检查或在出生后进行新生儿超声心动图检查。结果正常胎儿335例,NT或NF增厚者9例,其中1例在妊娠13周诊断心脏永存动脉干畸形,引产后病理证实,2例选择14周前终止妊娠,2例妊娠中期超声筛查胎儿其他结构异常选择中期引产,无心脏结构异常,4例足月分娩,无心脏结构异常。正常胎儿舒张早期时间(EADT)较舒张晚期时间(ENDT)短,左右心室之间无统计学差异。NT增厚不伴心脏畸形胎儿仅部分胎儿静脉导管搏动指数(PI)、阻力指数(RI)、收缩期峰值流速与舒张期最低流速比值(S/D)增高。永存动脉干胎儿左右心室E/A比值较正常胎儿异常增高或下降,EADT缩短,ENDT延长,EADT/ENDT比值缩小,静脉导管血流波形异常。结论妊娠13周后,随着胎儿心脏各个切面的显示率不断增高,可有针对性地对特殊群体进行早期的胎儿超声心动图检查,筛查严重的先天性心脏畸形。分析二尖瓣和三尖瓣的血流频谱,判断左右心室的血流动力学变化,并结合观察静脉导管的血流波形,可以辅助筛查胎儿先天性心脏畸形。如果仅二维超声怀疑心脏结构异常,而心内和心外血流动力学未发生改变者,应慎重诊断先天性心脏畸形,避免误诊。

Objective To observe the fetal cardial structure and characters of endocardiac and extracardiac haemodynamics parameters at the end of first trimester and the early phase of second trimester by 2-dimensional ultrasound and Doppler ultrasound,evaluate the value of Doppler ultrasound in screening the congenital cardiac defects（CCD）during this period.Methods General transabdominal ultrasonic exam was performed between 11＋0 and 14＋6 weeks′ gestation.Measure the thickness of nuchal translucency（NT）or soft tissue of neck,observe the fetal cardiac structure,and measure the blood flow of mitral valve,tricuspid valve and ductus venosus by Doppler ultrasound.Echocardiography were performed individually in second trimester or newborn stage.Results 335 fetuses were normal.9 fetuses with increased NT thickness or thickened soft tissue were found.5 cases were terminated in first or second trimester：1 fetus was diagnosed the persistent arterial trunk（PAT）in 13 gestational week and confirmed by autopsy,2 fetuses were found with extracardial abnormalities,2 fetuses were aborted considering the expectant mother′s will before 14 weeks′ gestation.4 fetuses without cardiac defects were delivered on full term.The early diastolic time（EADT）was shorter than the end diastolic time（ENDT）in normal fetus,there was no significant difference between left and right ventricles.Increased pulse index（PI）,resistant index（RI）,systolic and diastolic velocity ratio（S/D）of ductus venouses were observed in fetus with thickened NT and without CCD.Endocardiac and extracardiac hemodynamics parameter of the fetus with PAT were different from normal fetus,include the abnormal ratio of E/A,shortened EADT,prolonged ENDT,decreased ratio of EADT/ENDT,and an abnormal waveform of ductus venosus.Conclusions With the increasing of visualization of fetal heart after 13 weeks′ gestation,the fetus with the high risk of CCD could be performed the early fetal echocardiography exam for screening the severe CCD.To analyze the changes of endocardiac hemodynamics parameters,and observe the waveform of ductus venosus,which can screening the CCD helpfully.The diagnosis of CCD should be cautious if the cardiac abnormal structure is only observed in 2 dimentional ultrasound and there is no obvious changes in endocardiac and extracardiac hemodynamics parameters.