孕11～14周胎儿超声软指标在胎儿心脏结构评估中的价值

摘要

目的 探讨胎儿颈项透明层(NT)厚度、三尖瓣反流(TR)及静脉导管血流a波(DVa波)倒置等超声软指标在早孕期(孕11 ～14周)胎儿心脏结构评估中的价值.方法 2009年1月至2012年1月暨南大学附属第一医院胎儿医学科对孕11 ～14周4 673例胎儿进行超声检查,记录检查结果及妊娠结局,计算超声软指标在早孕期胎儿心脏结构检查中的假阳性率,以及对严重先天性心脏病(CHD)胎儿诊断的敏感度.结果 (1)CHD检查结果:4 673例胎儿中有31例产前超声诊断为CHD,其中17例在早孕期发现,5例在中孕期早期(15 ～ 16周)发现.31例产前超声诊断的CHD胎儿中有12例染色体异常(包括21三体5例、18三体2例、13 三体2例、Turner综合征2例、9号染色体倒位1例).(2)NT厚度与CHD产前诊断:4 673例胎儿中,NT厚度为第95～ 99百分位的胎儿206例(4.41％),有5例产前诊断为CHD,其中4例在孕早期诊断;NT厚度＜第95百分位的胎儿4 430例(94.80％),有16例产前诊断为CHD,其中5例在早孕期诊断;NT厚度＞第99百分位(即＞3.5 mm)的胎儿共37例(0.79％,37/4 673),有10例胎儿产前诊断为CHD,其中8例在早孕期诊断.(3)TR及DVa波倒置与CHD产前诊断:4 673例胎儿中TR 51例(1.09％),DVa波倒置98例(2.10％).31例产前诊断的CHD中,8例合并TR,7例合并DVa波倒置.(4)超声软指标对严重CHD检出的敏感度:31例产前诊断的CHD胎儿中,23例为严重CHD,早孕期任意一项超声软指标异常对检出严重CHD的敏感度为74％(17/23);NT厚度为第95 ～ 99百分位的诊断敏感度为22％(5/23),NT厚度＞第99百分位(即＞3.5 mm)者诊断敏感度为39％(9/23),TR的诊断敏感度为35％(8/23),DVa波倒置的诊断敏感度为30％ (7/23).(5)超声软指标对CHD检出的特异度:早孕期超声软指标检出CHD的特异度为:NT厚度为第95～99百分位时为4.30％ (201/4 673),NT厚度＞第99百分位时为0.58％(27/4 673),TR为0.92％ (43/4 673),DVa波倒置为1.94％ (91/4 673).结论 早孕期超声软指标中NT增厚、TR和DVa波倒置对胎儿心脏结构评估有很实用的临床价值,能检出大部分严重CHD,有利于产前更早期地作出CHD诊断.%Objective To evaluate the detection rate of congenital heart defect (CHD) during the first trimester screening for chromosomal abnormalities,the role of ultrasound soft markers including increased nuchal translucency (NT),tricuspid regurgitation (TR) and abnormal ductus venosus (DV) flow in the screening for cardiac anomalies was also investigated.Methods From January 2009 to January 2012,4 673 fetuses were scanned at 11-14 weeks at Department of Fetal Medicine,the First Affiliated Hospital of Jinan University.The ultrasound findings and follow up outcomes were recorded,False-positive rate of different first-trimester ultrasound markers for the detection of CHD was calculated,sensitivity of the markers for all major CHD was calculated as well.Results There was a significant association between major CHD and first trimester ultrasound markers.(1) Overall findings:among the 4 673 fetuses,31 fetuses were diagnosed CHD prenatally,17,12 and 2 of which were detected in the first,second and third trimester,respectively.In 22 of the 31 CHD cases,invasive procedure was performed,fetal karyotype was abnormal in 12 cases,including triosmy 21 (5 cases),trisomy 18 (2 cases),trisomy 13 (2 cases),Turner syndrome (2 cases) and pericentric inversion of chromosome 9 (1 cases).(2) NT measurement and prenatal detected CHD:in 4 673 cases,NT measurement between 95th-99th percentile were present in 206 (4.41％),5 cases were diagnosed CHD prenatally,in 4 of 5 cases were detected in first trimester; NT measurement ＜ 95th percentile were present in 4 430(94.80％),16 cases were diagnosed CHD prenatally,in 5 of 16 cases were detected in first trimester; NT measurement ＞ 99th percentile (＞ 3.5 mm) were present in 37 (0.79％,37/4 673),10 cases were diagnosed CHD prenatally,in 8 of 10 cases were detected in first trimester.(3) TR and inverted a-wave at the DV and prenatal detected CHD:among 4 673 cases,TR or inverted a-wave at the DV were present in 51 (1.09％),98 (2.10％) respectively.TR was present in 8 of 31 CHD cases,inverted a-wave at the DV was present in 7 of 31 CHD cases.(4)Sensitivity of different first trimester ultrasound markers for detection of major CHD cases:in 31 CHD cases diagnosed prenatally,23 eased were defined as major CHD.Sensitivity of at least one of the ultrasound narkers,NT measurement between 95th-99th percentile,＞ 99th percentile(＞ 3.5 mm),TR or inverted a-wave at the DV for detection of major CHD eases was 74％ (17/23),22％ (5/23),39％ (9/23),35％ (8/23),30％ (7/23),respectively.(5) Specificity of different first trimester ultrasound markers for detection of CHD cases:specificity of NT measurement between 95th-99th percentile,＞ 99th percentile(＞ 3.5 mm),TR or inverted a-wave at the DV for detection of major CHD cases was 4.30％ (201/4 673),0.58％ (27/4 673),0.92％ (43/4 673),1.94％ (91/4 673).Conclusions Routine first trimester soft markers for chromosomal abnormalities screening combined with cardiac assessment can detect quite a number of major heart defects.Increased NT,TR and abnormal DV flow can be important indicators for echocardiography,which is favorable to early prenatal diagnosis of CHD.