Ductus Venosus Blood Flow Assessment Research Articles

Screening performances of abnormal first-trimester ductus venosus blood flow and increased nuchal translucency thickness in detection of major heart defects.

The aim of this study was to evaluate the screening performances of abnormal ductus venosus (DV) blood flow for the detection of heart defects in chromosomally normal fetuses with increased nuchal translucency (NT) thickness at 11-13 + 6 weeks' gestational in a population of singleton pregnancies. During an 8-year period, all singleton pregnancies from 11 + 0 to 13 + 6 weeks were scanned for NT and DV blood flow assessment. Two groups of cases with abnormal NT were evaluated: NT ≥ 95th and NT ≥ 99th centile. DV waveforms were considered to be abnormal if the a-wave was reversed or absent (R/A). Addition of DV R/A a-wave to either NT ≥ 95th or NT ≥ 99th percentile increased specificity (p < 0.001 and p < 0.001, respectively), but not screening performances in detection of major heart defects (p = 0.73 and p = 0.91, respectively). Combination of DV R/A a-wave with NT ≥ 95th or NT ≥ 99th centile correlated with right heart defects (p = 0.024 and p = 0.013, respectively). In chromosomally normal fetuses, addition of abnormal DV a-wave to increased NT does not improve screening performances of NT in detection of major hearts defects in first trimester. However, there is correlation of such parameter with right heart defects and AV septal defects.

Abnormal first‐trimester ductus venosus blood flow: a marker of cardiac defects in fetuses with normal karyotype and nuchal translucency

To evaluate the independent contribution of ductus venosus (DV) blood flow assessment at 11-14 weeks' gestation to the prediction of congenital heart defects (CHD) in chromosomally normal fetuses, irrespective of the value of the nuchal translucency thickness (NT). During a 4-year period, all singleton pregnancies from 11 + 0 to 13 + 6 weeks' gestation were scanned for NT and DV blood flow in a tertiary center. Abnormal DV blood flow was defined as either absent or reversed flow during atrial contraction (AR-DV). Fetal echocardiography was performed in all cases with either NT > 99(th) percentile or AR-DV. Follow-up was assessed by postnatal examination or autopsy in cases of termination of pregnancy or perinatal death. A total of 6120 pregnancies were scanned at a median gestational age of 12 weeks, and 45 cases of CHD were detected. AR-DV was found in 206 fetuses, of which 145 (70.4%) had a normal karyotype. Among fetuses with AR-DV and normal karyotype, 11 cases of CHD were diagnosed, giving a sensitivity of 24.4%, a positive predictive value of 7.6% and an odds ratio of 9.8. Increased NT (> 99(th) centile) was present in 55 of the 145 (37.9%) cases with AR-DV and normal karyotype, and in 6/11 (54.5%) of those with CHD. Thus, the group of 90 fetuses with abnormal DV blood flow and normal NT contained five cases of CHD, for a sensitivity of 11.1%, a positive predictive value of 5.5% and an odds ratio of 8.5. Right-heart anomalies were predominant in those cases with isolated AR-DV (4/5), but no specific CHD pattern was found in those with increased NT. The detection rate of CHD by the combined use of increased NT and/or AR-DV in the first trimester improved from 28.9% (13/45) to 40.0% (18/45). In experienced hands, abnormal DV blood flow in the first trimester is an independent predictor of CHD and should constitute an indication for early echocardiography. In this study, the use of DV blood flow assessment increased early detection of CHD by 11% with respect to the use of NT measurement alone.

Screening for twin–twin transfusion syndrome at 11–14 weeks of pregnancy: the key role of ductus venosus blood flow assessment

A discrepancy in crown-rump length (CRL) and/or nuchal translucency thickness (NT) between monochorionic twins has been found to be associated with an increased risk of twin-twin transfusion syndrome (TTTS). As one of the most plausible mechanisms for increased NT is hemodynamic imbalance and cardiac dysfunction, indirectly manifested by abnormal blood flow in the ductus venosus (DV), we aimed to clarify the role of DV blood flow assessment in identifying those monochorionic twins more prone to develop TTTS. We present 99 cases of monochorionic diamniotic twin pregnancies in which CRL, NT and DV blood flow were evaluated at 11-14 weeks' gestation. Discrepant values of CRL were not predictive of TTTS development. Intertwin NT discrepancy >or= 0.6 mm had a sensitivity of 50.0% and a specificity of 92.0%. The presence of at least one abnormal blood flow waveform in the DV was associated with a relative risk for developing TTTS of 11.86 (95% CI, 3.05-57.45), with a sensitivity of 75.0% and a specificity of 92.0%. The combination of abnormal DV blood flow with NT discrepancy >or= 0.6 mm yielded a relative risk for the development of TTTS of 21 (95% CI, 5.47-98.33). Both intertwin discrepancy in NT and abnormal flow in the DV in monochorionic twins may represent early manifestations of hemodynamic imbalance between donor and recipient. In these pregnancies, in addition to NT measurement at 11-14 weeks, the Doppler assessment of DV blood flow significantly increases the performance of screening for those at risk of developing TTTS.

P01.27: The role of ductus venosus blood flow assessment in screening for chromosomal abnormalities at 10–14 weeks of gestation

P01.27: The role of ductus venosus blood flow assessment in screening for chromosomal abnormalities at 10–14 weeks of gestation

Ductus venosus blood flow assessment at 11 to 14 weeks of gestation and fetal outcome.

To evaluate the association between abnormal ductus venosus (DV) at 11-14 weeks' gestation and chromosomal abnormalities, structural defects and fetal outcome. DV flow-velocity waveform (DV-FVW) and nuchal translucency thickness (NT) were prospectively evaluated in 1217 singleton pregnancies. The DV-FVW was abnormal in 84 fetuses, NT was above the 95th centile in 160 fetuses and both markers were observed in 41 fetuses. Chromosomal defects were diagnosed in 22 fetuses. The sensitivity, specificity and positive and negative predictive values for an abnormal karyotype were 86.4%, 86.9%, 11.9% and 99.7%, respectively, for an increased NT. These values were 68.2%, 96.9%, 31.3% and 99.3%, respectively, for DV-FVW abnormalities and 68.2%, 97.6%, 36.6% and 99.3%, respectively, when both markers were found simultaneously. Regarding structural defects, these values were 43.8%, 92.9%, 8.3% and 99.1% for an abnormal NT, 25.0%, 92.6%, 4.8% and 98.8% for DV-FVW abnormalities and 25.0%, 97.9%, 15.4% and 98.9% for both together. Considering those cases of unexplained fetal demise, the values were 44.4%, 85.9%, 5.0% and 98.9% for NT abnormalities, 22.2%, 92.6%, 4.8% and 98.6% for an abnormal DV-FVW and 22.2%, 98%, 15.4% and 98.7% for both. In cases with increased NT, the percentage of live births with normal karyotype and no major fetal structural defects decreased from 93.8% in normal DV-FVW fetuses to 77.3% in abnormal ones. DV assessment at 11-14 weeks' gestation is useful in screening for fetal chromosomal abnormalities and may help to reduce the false-positive rate when combined with NT measurement. Abnormal DV-FVW is also associated with an increase in adverse perinatal outcome in fetuses with enlarged NT. However, the value of DV-FVW assessment in cases with normal NT is unclear.

OC046: The use of nuchal translucency screening in women of 36 years and older: uptake and effects on invasive testing rate

Objective: To evaluate the effectiveness of combined fetal screening by nuchal translucency (NT) thickness and ductus venosus blood flow assessment for the detection of chromosomal abnormalities. Methods: NT measurements and ductus venosus (DV) blood flow were prospectively evaluated in 839 consecutive fetuses between 11 and 14 weeks of gestation. Reverse or absent flow during atrial contraction in DV was defined abnormal. In 221 fetuses CVS was performed to analyse fetal karyotype. Fetal outcome was assessed by a written questionnaire of the obstetricians and in the liveborn postnatal outcome was obtained by neonatal assessment. The effectiveness for the detection of fetal chromosomal abnormality was calculated for NT measurement, DV blood flow assessment and the combined approach using the DV assessment as a second line test in fetuses with increased NT. Results: Karyotype was abnormal in 53 fetuses, NT-thickness was above the 95. percentile in 114 fetuses and DV blood flow pattern were abnormal in 52 fetuses. In the study population screen positive rate, sensitivity, specificity, positive predictive value and negative predictive value of abnormal DV flow pattern for chromosomal abnormality were 6.2%, 45.3%, 96.4%, 46.1%, and 96.3%. In this population NT screening yielded 13.6%, 84.9%, 39.5%, 98.9%, respectively. The corresponding values for the combined approach were 3.8%, 39.6%, 98.6%, 65.6% and 97.0%, respectively. Conclusions: DV blood flow assessment can be performed to screen for chromosomal abnormalities in fetuses at 11–14 weeks gestation. Our results suggest that the combined screening by NT and DV blood flow measurement yielded substantially lower detection rates of chromosomal abnormalities.

OC045: Does ductus venosus blood flow assessment in addition to nuchal translucency measurements offer an improved screening of abnormal fetal karyotype?

OC045: Does ductus venosus blood flow assessment in addition to nuchal translucency measurements offer an improved screening of abnormal fetal karyotype?

Ductus venosus blood flow assessment at 10–16 weeks' gestation and chromosomal abnormalities

Background: Enlarged fetal nuchal translucency (NT) is a well established ultrasonographic marker for aneuploidy screening, especially during the first trimester of gestation. Nuchal translucency screening combined with maternal age at early mid‐trimester can identify about 75–80% of chromosomal abnormalities with a false–positive rate of 5%. Recently, Doppler parameters have been included in fetal aneuploidy screening, in order to improve the test performance. Changes in the ductus venosus (DV) blood flow velocity waveforms have been reported in a significant proportion of chromosomally abnormal fetuses at first and early mid‐trimester of pregnancy.Objective: The aim of our study was to evaluate the role of the DV blood flow assessment at 10–16 weeks' gestation in the screening for chromosomal abnormalities.Methods: From December 1998 to June 2001, DV blood flow was prospectively evaluated in 5067 consecutive pregnancies between 10 and 16 weeks of gestation. Pulsatility index for the DV (DVPI) was calculated. All cases were screened for chromosomal defects combining maternal age and fetal NT thickness.Results: The average maternal age was 32 years (range 22–47). Seventy‐four percent of the women were younger than 35. The incidence of chromosomal abnormalities was 1.06% (n = 54), including trisomy 21 (n = 25), trisomy 18 (n = 6), trisomy 13 (n = 2) and others (n = 21). The incidence of chromosomal abnormalities was 13.8% in those cases where DVPI was greater than the 95th centile, compared with an incidence of 0.3% in the remaining cases with a DVPI below this cut‐off. This fact gives and odds ratio (OR) of 48 (95% IC: 26–87). The overall detection rate (DR), specificity (S), positive predictive value (PPV) and negative predictive value (NPV) for chromosomal abnormalities were 70.4, 95.3, 13.8, and 99.7%, respectively, when using the 95th centile DVPI as a cut‐off. According to gestational age, all the statistical parameters were increased in early gestational age (10–13 weeks) when comparing with late gestational age (14–16 weeks), the corresponding DR and OR being 76.3% and 64 (95% CI: 30–138) compared with 56.3% and 26 (95% CI: 9–72), respectively. Moreover, when only autosomal trisomies were considered, a DR of 87.9% was reached with an S, PPV, NPV and OR of 95.3, 10.9, and 99.9% and 146 (95% CI: 51–418).Conclusions: Our results suggest that the evaluation of DVPI at 10–16 weeks' gestation is a useful tool in the screening for chromosomal defects, especially in detecting autosomal trisomies and when it is assessed in early gestational age.

The role of ductus venosus blood flow assessment in screening for chromosomal abnormalities at 10-16 weeks of gestation.

To evaluate the role of ductus venosus blood flow assessment at 10-16 weeks' gestation in screening for chromosomal abnormalities. Ductus venosus blood flow was prospectively evaluated in 1371 consecutive pregnancies between 10 and 16 weeks of gestation. The pulsatility index for veins was calculated. All cases were screened for chromosomal defects combining maternal age and fetal nuchal translucency thickness. A chromosomal abnormality was found in 20 cases. The overall detection rate, specificity, positive predictive value, negative predictive value and odds ratio for chromosomal abnormalities were 65%, 95.7%, 18.3%, 99.5% and 41 (95% CI 16-108), respectively, when using the 95th centile pulsatility index as a cut-off. These preliminary results suggest that evaluation of the ductus venosus pulsatility index at 10-16 weeks' gestation is a useful second-line screening test for chromosomal defects. A combination of nuchal translucency measurement and ductus venosus assessment might increase specificity while maintaining an optimal detection rate for chromosomal abnormalities. Such a policy could identify 55% of all chromosomal abnormalities and about 69% of autosomal trisomies, reducing the need for invasive testing to less than 1%.

Anticipating twin-twin transfusion syndrome in monochorionic twin pregnancy. Is there a role for nuchal translucency and ductus venosus blood flow evaluation at 11-14 weeks?

Twin-twin transfusion syndrome is a major complication of monochorionic twin pregnancies. In foetuses from monochorionic twinning the presence of increased nuchal translucency thickness (NT) has been associated with an increased risk of developing this syndrome. One of the presumed mechanisms of increased NT is early cardiac failure, indirectly indicated by abnormal blood flow in the ductus venosus. We present eleven cases of monochorionic twin pregnancies in which nuchal translucency thickness and ductus venosus blood flow evaluation was performed at 11-14 weeks. In the two cases presenting with nuchal translucency discrepancy between the two foetuses along with anomalous ductus venosus blood flow in the foetus with increased nuchal translucency, twin-twin transfusion syndrome (TTTS) eventually developed. In none of the twins displaying no inter-twin difference in NT measurements and in those with discrepant NT but normal flow in both ductus venosus, was the progression to TTTS observed. In the two cases which developed TTTS, foetoscopic laser coagulation of the vascular anastomosis was successfully carried out at 18 weeks and normalisation of the venous return was registered. These findings suggest that the association of increased NT and abnormal flow in the ductus venosus in monochorionic twins may be an early manifestation of haemodynamic imbalance between the donor and the recipient eventually manifested as twin-twin transfusion syndrome. Further studies, however, are necessary to establish the potential role of the combination of NT and ductus venosus blood flow assessment as a screening method for TTTS.