Ductus Venosus Flow Velocity Waveforms Research Articles

Ductus venosus Doppler waveform pattern in fetuses with early growth restriction.

We aimed to assess if maximum velocities of the ductus venosus flow velocity waveform are associated with adverse outcomes in early-onset fetal growth restriction. Retrospective cohort study from two tertiary referral units, including singleton fetuses with estimated birthweight or fetal abdominal circumference ≤10th centile and absent or reversed end-diastolic velocity in the umbilical artery delivered between 26+0 and 34+0 weeks of gestation. Pulsatility index for veins, and maximum velocities of S-, D-, v- and a-waves, were measured in the ductus venosus within 24hours of birth. Logistic regression was used to describe the relation between severe neonatal morbidity or neonatal death and clinical independent predictors. The study population included 132 early-onset fetal growth restriction fetuses. Newborns with neonatal morbidity or neonatal death had significantly lower values of v/D maximum velocity ratio multiples of the median (0.86 vs 095; P=0.006) within 24hours of birth. The v/D ratio remained a significant predictor of neonatal death or severe neonatal morbidity after adjusting for gestational age and birthweight (adjusted odds ratio 0.065, 95% confidence interval 0.004-0.957). Assessment of ductus venosus v/D maximum velocity ratio might help to identify fetal growth restriction fetuses at increased risk for neonatal death or severe neonatal morbidity. Confirmation in prospective studies is necessary.

EP04.06: Systolic and diastolic time interval ratios of the ductus venosus flow velocity waveform in fetal growth restriction

EP04.06: Systolic and diastolic time interval ratios of the ductus venosus flow velocity waveform in fetal growth restriction

Cardiac defects, nuchal edema and abnormal lymphatic development are not associated with morphological changes in the ductus venosus

BackgroundIn human fetuses with cardiac defects and increased nuchal translucency, abnormal ductus venosus flow velocity waveforms are observed. It is unknown whether abnormal ductus venosus flow velocity waveforms in fetuses with increased nuchal translucency are a reflection of altered cardiac function or are caused by local morphological alterations in the ductus venosus. AimThe aim of this study was to investigate if the observed increased nuchal translucency, cardiac defects and abnormal lymphatic development in the examined mouse models are associated with local changes in ductus venosus morphology. Study designMouse embryos with anomalous lymphatic development and nuchal edema (Ccbe1−/− embryos), mouse embryos with cardiac defects and nuchal edema (Fkbp12−/−, Tbx1−/−, Chd7fl/fl;Mesp1Cre, Jarid2−/−NE+ embryos) and mouse embryos with cardiac defects without nuchal edema (Tbx2−/−, Fgf10−/−, Jarid2−/−NE− embryos) were examined. Embryos were analyzed from embryonic day (E) 11.5 to 15.5 using markers for endothelium, smooth muscle actin, nerve tissue and elastic fibers. ResultsAll mutant and wild-type mouse embryos showed similar, positive endothelial and smooth muscle cell expression in the ductus venosus at E11.5–15.5. Nerve marker and elastic fiber expression were not identified in the ductus venosus in all investigated mutant and wild-type embryos. Local morphology and expression of the used markers were similar in the ductus venosus in all examined mutant and wild-type embryos. ConclusionsCardiac defects, nuchal edema and abnormal lymphatic development are not associated with morphological changes in the ductus venosus. Ductus venosus flow velocity waveforms most probably reflect intracardiac pressure.

Absence of an anatomical origin for altered ductus venosus flow velocity waveforms in first‐trimester human fetuses with increased nuchal translucency

To perform a morphological evaluation of the ductus venosus, heart and jugular lymphatic sac (JLS) in first-trimester human fetuses with normal and abnormal ductus venosus flow velocity waveforms (DV-FVWs) and normal and increased nuchal translucency (NT). Postmortem examination was performed on fetuses with increased NT or structural malformations with previous NT and DV-FVW measurements. Ductus venosus morphology was examined using markers for endothelium, smooth muscle actin (SMA), nerves and elastic fibers. Fetal hearts were studied by microscopy. The nuchal region was analyzed using markers for lymphatic vessels, endothelium, SMA and nerves. Two trisomy 21 and two trisomy 18 fetuses with increased NT and abnormal DV-FVWs were analyzed. As a control, one euploid anencephalic fetus with normal NT, cardiac anatomy and DV-FVWs was examined. Similar endothelial and SMA expression was observed in the ductus venosus in all fetuses. Nerve and elastic fiber expression were not detected. Three trisomic fetuses showed cardiac defects, one trisomic fetus demonstrated normal cardiac anatomy. The JLS was abnormally enlarged or contained red blood cells in all trisomic fetuses. The control fetus showed a normal JLS. Abnormal DV-FVWs are not justified by alterations in ductus venosus morphology. DV-FVWs most probably reflect intracardiac pressure. © 2016 John Wiley & Sons, Ltd.

Alterations in time intervals of ductus venosus and atrioventricular flow velocity waveforms in growth-restricted fetuses.

To investigate time intervals of the ductus venosus (DV) flow velocity waveform (FVW) and those of the cardiac cycle that correspond with each DV-FVW component in fetuses with intrauterine growth restriction (IUGR) due to placental insufficiency. Women with a pregnancy complicated by IUGR were recruited into the study, as was a normal control group. Time intervals for systolic (S) and diastolic (D) components were measured in DV-FVW as follows: S(DV), from the nadir of the a-wave during atrial contraction to the nadir between the S-wave and D-wave; D(DV), from the nadir between S-wave and D-wave to the nadir of the a-wave. Regarding cardiac cycles, the following variables were measured from ventricular inflow through the tricuspid valve (TV) and mitral valve (MV): S(TV) and S(MV), from the second peak of ventricular inflow caused by atrial contraction (A-wave) to the opening of the atrioventricular valve; D(TV) and D(MV), from the opening of the atrioventricular valve to the peak of the A-wave. In the IUGR group, only the last examination performed within 1 week of delivery was used for analysis. All variables were analyzed statistically using Z-scores. Data were obtained from 249 normal fetuses and 26 fetuses with IUGR. Compared to normal fetuses, S(DV) showed a significant decrease (P < 0.001), while D(DV) showed a significant increase (P < 0.001) in the IUGR group. Regarding cardiac cycles, S(TV) and S(MV) showed significant decreases (P = 0.014 and P < 0.001, respectively) and D(TV) and D(MV) showed significant increases (P = 0.008 and P = 0.002, respectively) in fetuses with IUGR. Time-interval alterations of DV-FVW in growth-restricted fetuses reflect the hemodynamic events caused by placental insufficiency.

P13.05: Longitudinal change of time intervals of ductus venosus in growth restricted fetuses

To investigate the sequential changes of time intervals of ductus venosus (DV) flow velocity waveform (FVW) in fetuses with growth restriction (FGR). Time intervals of systolic (S) and diastolic (D) components of DV-FVW were measured in FGR fetuses. We also calculated the pulsatility index (DV-PI) and the ratio of S to D (S/D ratio). Longitudinal study of FGR fetuses was performed and each index was compared to the reference range. FGR was defined as the estimated fetal weight below -2.0 standard deviation of local standard with elevated umbilical artery pulsatility index more than 95 percentile of the normal reference range. A total of 35 observations were performed (median, 6; range, 3-13) on 5 FGR fetuses. The median gestational age at inclusion and delivery were 25.1 (range, 22.3-27.7) weeks and 28.9 (range, 27.1-30.1) weeks. In FGR fetuses, S/D ratios became lower than the 5th percentile of the normal mean at the median of 20 days (range, 17-46) before delivery and showed almost linear deterioration throughout monitoring. DV-PI of FGR became higher than normal fetuses at the median of 20 days (range, 3-21) before delivery, which was almost the same as S/D ratio, however, S/D ratio seemed to show abnormal values several days earlier than DV-PI in some of the cases. Time intervals of systolic and diastolic phases and their ratio might add some insight to indices already established such as the DV-PI in evaluation of DV-FVW. Further study is needed for of these variables into clinical practice.

The role of maternal & fetal doppler in pre-eclampsia.

Pre-eclampsia is associated with significant maternal and fetal morbidity and mortality worldwide. Pregnancy complicated by preeclampsia and/or by fetal growth restriction are reported to have inadequate maternal vascular responses to placentation. This defective vascular response was due to the failure of second wave of endovascular trophoblast migration leading to both a reduced amount and depth of trophoblast invasion of myometrium followed by the development of placental hypoxia and ischemia that can be measured biophysically by means of Doppler Ultrasound. The role of Doppler in the screening and management of preeclampsia would be reviewed in here focusing on uterine artery, umbilicalartery (UA), middle cerebral artery (MCA) and ductus venosus (DV) waveforms. The commonly used flow velocity waveform (FVW) spectrum is used namely resistance index (RI), systolic/diastolic ratio (S/D) or pulsatility index (Pl). The presence or persistence of an early diastolic notch of uterine artery over 24 weeks of pregnancy is predictive of subsequent preeclampsia and or IUGR later on. Umbilical artery Pl falls with gestational age, although mean Pl is relatively stable after 30 weeks gestation. While elevated indices are predictive of adverse outcome, absent or reversed end-diastolic velocities (AREDV) are of particular significance for growth restriction. Mean MCA Pl increases to approximately 28weeks gestation and then falls to term. Progressive hypoxemia results in a reduction in MCA Pl and therefore values 5th centile are regarded as abnormal. The ratio of UA/MCA Pl has been widely used as an index of cerebral redistribution. The 9 51h centile for pulsatility index for vein (PIV) of ductus venosus FVW falls from 0.9 at 20 weeks to 0.7 at term, with values above this being regarded as abnormal. The absence or reversal of atrial systolic forward flow of DV FVW are of particular clinical significance. By using Doppler in the early detection of preeclampsia and its fetal complication namely growth restriction we can arrange the management decisions and monitoring strategy for preeclampsia.

Reference ranges for time-related analysis of ductus venosus flow velocity waveforms in singleton pregnancies

To investigate time intervals of ductus venosus (DV) flow velocity waveforms (FVW) in correlation to fetal heart rate and gestational age and to construct reference ranges for the second and third trimester. Furthermore, we investigate time intervals of FVW through the tricuspid valve. Flow velocity waveforms of the DV and through the tricuspid valve were recorded in 135 normal singleton fetuses between 17 and 38 weeks' gestation. Time intervals for systolic (S) and early diastolic (D) peaks were analyzed regarding acceleration time (acc-S for S, acc-D for D) and deceleration time (dec-S for S, dec-D for D), respectively. Similarly, time intervals for both peaks of right ventricular inflow were analyzed regarding acceleration time (acc-E for E-wave, acc-A for A-wave) and deceleration time (dec-E for E-wave, dec-A for A-wave), respectively. In the DV, acc-D and dec-D increased significantly with gestational age. In tricuspid valve, acc-E and acc-A showed a significant increase with gestational age. All parameters except acc-S showed significant negative correlations with fetal heart rate. With advancing gestational age, prolongation of the diastolic phase of DV-FVW and of the E-wave of tricuspid flow was observed, suggesting maturation of ventricular diastolic function. Time-related analysis of Doppler signals of DV-FVW may provide detailed insights into fetal cardiac function.

OP36.03: Time‐related analysis of ductus venosus flow velocity waveforms in normal fetuses and intrauterine growth restriction

OP36.03: Time‐related analysis of ductus venosus flow velocity waveforms in normal fetuses and intrauterine growth restriction

Time-related analysis of ductus venosus flow velocity waveforms in normal singleton pregnancies

Time-related analysis of ductus venosus flow velocity waveforms in normal singleton pregnancies

Ductus Venosus Doppler for Fetal Surveillance in High-risk Pregnancies

Doppler evaluation of the fetal ductus venosus has increased our depth of understanding of many fetal conditions. The ductus venosus has an important role in the regulation of nutrient partitioning in the fetus. Alterations in cardiac afterload, contractility compliance, intravascular volume status, and heart rate may significantly impact on the ductus venosus flow velocity waveform. Accordingly, ductus venosus Doppler is useful in the management of conditions that put the fetus at risk for cardiovascular deterioration. The application of DV Doppler in fetal growth restriction, complicated monochorionic multiple gestation, fetal hydrops, and arrhythmia are discussed in this review.

Ultrasound Markers of Chromosomal Anomalies in the First Trimester

ABSTRACT Chromosomal anomalies are associated with considerable morbidity and mortality. The protocol for identifying these fetuses had for many years included a single clinical criterion of maternal age. Advances in biochemical screening combined with the excellent display of fetal dysmorphology afforded by technological advances in ultrasound equipment have resulted in a paradigm shift in the diagnosis of chromosomal abnormalities in the fetus, from the second trimester to the late first trimester. The accuracy of diagnosis as reported in multiple large series has pushed both screening and diagnostic testing for chromosomal disorders to the window now referred to as the 11 to 13 weeks + 6 days scan. Recent data have shown chorion villus sampling after 10 weeks to be as safe in experienced hands as amniocentesis and this has pushed the advantages of first trimester screening further. Ultrasound parameters for the detection of Down's syndrome in the first trimester include the nuchal translucency (NT) as the most well-defined and studied parameter, evaluation of the nasal bone (NB), frontomaxillary facial (FMF) angle, ductus venosus (DV) flow velocity waveform, tricuspid regurgitation (TR) and fetal heart-rate. Each parameter has well-defined criteria to be fulfilled for accurate quantification. Biochemical parameters that are currently in wide use include PAPP-A and free beta-hCG. Other parameters that the software accounts for are the gestational age assessed by the crown-rump length, maternal age, ethnicity, smoking, IVF and number of fetuses with chorionicity. Combining maternal age, biochemistry, NT and NB between 11 to 13 weeks + 6 days yields a detection rate of 96% with a false positive rate of 5%.

OP24.04: Time‐related analysis of ductus venosus flow velocity waveforms in normal singleton pregnancies

the inferior vena cava was 87.1o (range 52–130o). Both angles were constant during pregnancy. The size of the angle between the rt. hepatic and ductus is 45% of that between the angle of rt, hepatic and IVC. Two groups were defined according to gestational age: 13–19 weeks gestation (99 women) and 20–30 weeks of gestation (84 women). The angles between the rt. hepatic to the ductus venosus and IVC were 37.6o and 85.7o, respectively, in the first group; 40.9o and 87.8o at second trimester. There were no significant differences in the angles between the 2 groups Conclusions: The geometrical arrangement of the abdominal venous return to the atrium is constant throughout pregnancy. We believe that knowledge of this arrangement can assist in evaluation of abnormal venous return to the rt. atrium.

Influence of nuchal cord on ductus venosus assessment at 11 to 13 + 6 weeks' gestation

To assess the influence of the presence of nuchal cord (NC) on the evaluation of the fetal ductus venosus flow velocity waveform (DV-FVW). This prospective study included 1174 normal non-selected singleton pregnancies between 11 and 13 + 6 weeks' gestation. We recorded the presence or absence of NC around the fetal neck, and assessed its relationship with the qualitative assessment and quantitative measurement of the DV-FVW. We observed NC around the fetal neck in 6.73% of cases and detected reversed flow of the a-wave of the DV-FVW in 2.98% of cases. In the group without NC, 21 of 1095 had reversed flow in the DV-FVW (1.9%; 95% CI, 1.28-3.02), whereas in the group with NC, 14 of 79 had reversed flow in the DV-FVW (17.7%; 95% CI, 16.67-40.35). We found a lower pulsatility index in fetuses without NC in comparison to those with NC (P < 0.001). We also found an association between the presence of NC and an increased occurrence of absent and reversed a-wave of the flow velocity waveforms (P < 0.001). On multivariate logistic regression analysis, a much higher occurrence of reversed DV-FVW a-wave was detected in fetuses with NC and smaller crown-rump length, and a much higher occurrence of absent DV-FVW a-wave was found in fetuses with NC and a higher maternal body mass index. The presence of NC modifies the sonographic findings in the qualitative and quantitative evaluation of the DV-FVW.

Amniotic Fluid and Maternal Blood Characteristics in Severe Mid-Trimester Twin–Twin Transfusion Syndrome

Objective: To investigate the concentrations of metabolic variables in the amniotic fluid of the recipient twin and maternal blood and to correlate them with clinical features, which are characteristic for the course of pregnancies with twin–twin transfusion syndrome (TTS). Materials and Methods: In 109 pregnancies with severe mid-trimester TTS, we measured the concentrations of interleukin-6 (IL-6), α-fetoprotein (AFP), sodium, potassium, total protein, β₂-microglobulin and osmolality in the amniotic fluid of the recipient twin prior to laser coagulation of the vascular anastomoses and compared them to a control group of 92 singleton pregnancies. We measured the pulsatility index (PI) of ductus venosus flow velocity waveforms in the recipient twin and performed a retrospective chart analysis for complete maternal blood count before and after the procedure. Results: All variables, except osmolality, IL-6 and AFP were significantly lower in the TTS group. There was a significant positive correlation between PI in the ductus venosus and the amniotic fluid AFP concentrations (r = 0.355; p < 0.001). There was a significant fall in complete maternal blood count after laser therapy (p < 0.001) and a significant correlation between the amount of amniotic fluid drained and the fall of maternal Hb (r = –0.261; p = 0.03) and hematocrit (r = –0.212; p = 0.01). Conclusion: Pathophysiologic changes in TTS do not only occur at the inter-twin level of placental vascular anastomoses but also at the materno-fetal level of fluid exchanges. AFP is correlated to the severity of congestive heart failure of the recipient twin.

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.

The role of fetal nuchal translucency and ductus venosus Doppler at 11-14 weeks of gestation in the detection of major congenital heart defects.

To determine whether, in a selected high-risk population, Doppler velocimetry of the ductus venosus can improve the predictive capacity of increased nuchal translucency in the detection of major congenital heart defects in chromosomally normal fetuses at 11-14 weeks of gestation. Ductus venosus Doppler ultrasound blood velocity waveforms were obtained prospectively at 11-14 weeks of gestation in 1040 consecutive singleton pregnancies. Waveforms were classified either as normal in the presence of a positive A-wave, or as abnormal if the A-wave was absent or negative. All cases were screened for chromosomal defects by a combination of maternal age and fetal nuchal translucency thickness. In 484 cases karyotyping was performed. Those fetuses found to be chromosomally normal by prenatal cytogenetic analysis, and which had abnormally increased nuchal translucency and/or abnormal ductus venosus Doppler velocimetry, underwent fetal echocardiography at 14-16 weeks of gestation. Ultrasound examination was repeated at 22-24 weeks of gestation in all women. The sensitivity, specificity and positive and negative predictive values for the detection of major cardiac defects of increased nuchal translucency thickness alone, ductus venosus Doppler alone and increased nuchal translucency thickness in association with abnormal ductus venosus Doppler were determined. In 29 of 998 fetuses presumed to be chromosomally normal, reversed or absent flow during atrial contraction was associated with increased (> 95(th) centile for crown-rump length) nuchal translucency. Major cardiac defects were observed in 9 of these 29 fetuses. No other major cardiac abnormalities were found in chromosomally normal fetuses in spite of the presence of either increased nuchal translucency alone or abnormal ductus venosus velocimetry. A total of 25 cardiac malformations were observed in the population. Fifteen were associated with aneuploidy and 10 fetuses had a normal karyotype. Nine of the 10 had major cardiac anomalies and one had a ventricular septal defect. The nine cases with normal karyotype and major cardiac anomalies had both increased nuchal translucency and abnormal ductus venosus flow velocity waveforms. In chromosomally normal fetuses with increased nuchal translucency, assessment of ductus venosus blood flow velocimetry could improve the predictive capacity for an underlying major cardiac defect.

659 Ductus venosus flow velocity waveforms in fetuses with enlarged nuchal translugency in relation with the found cardiac malformations

659 Ductus venosus flow velocity waveforms in fetuses with enlarged nuchal translugency in relation with the found cardiac malformations

Ductus venosus blood flow in chromosomally abnormal fetuses at 11 to 14 weeks of gestation

This article reviews the role of ductus venosus (DV) Doppler evaluation in the screening for aneuploidies at 11 to 14 weeks of gestation. Ductus venosus flow velocity waveforms were obtained immediately before fetal karyotyping in 515 consecutive singleton pregnancies at 11 to 14 weeks. We found 446 normal and 69 abnormal karyotypes. Abnormal flow in the DV was the only significant difference between both groups. Sensitivity of the test was 80% and false positive rate < 1%. Normal karyotype but abnormal flow in the DV was recorded in 17 of 446 cases, 7 presenting a cardiac defect. Increased nuchal translucency seems to be related, in most cases, to early cardiac dysfunction. Chromosomal abnormalities and/or cardiac defects were often found in cases with increased nuchal translucency and abnormal flow in the DV. We suggest that the evaluation of ductal flow between 11 to 14 weeks of gestation should be adopted as a second level screening test to reduce invasive test rate derived from the exclusive measurement of nuchal translucency.

F37Serial measurements of ductus venosus flow velocity waveforms and nuchal translucency thickness: relationship with fetal outcome

BackgroundIn a previous study we have demonstrated that a statistically significant relationship exist between nuchal translucency (NT) thickness and ductus venosus flow measurements. Moreover we have shown that a decrease in NT thickness at a subsequent examinationl reduces the chance of an abnormal outcome. The aim of this study was to investigate the interrelationship between NT thickness and ductus venosus Doppler measurement (a‐wave, pulsatility index PI) at repeated examinations and their relationship with fetal outcome.MethodDuctus venosus flow velocity waveforms and NT thickness were measured twice (median 4 days range 2–7) in 36 fetuses with increased nuchal thickness.ResultsAccording to the behaviour in the two parameters the fetuses were divided into three categories: unchanged both abnormal (1), unchanged only NT persistently abnormal (2) and changed NT decreased. The fetuses in group 1 had a 20 fold increase chance of an abnormal outcome (chromosomal anomalies, unexplained intrauterine death, congenital anomalies, cardiac defects n.). Conversely fetuses in group 3 had a lower chance of an abnormal outcome than group 1 and 2.ConclusionIn fetuses with normal karyotype the finding of persistently increased NT and ductus venosus flow represents a poor prognostic factor, more than when nuchal translucency alone is persistently abnormal.