Prenatal diagnosis of ductus venosus agenesis and its association with cytogenetic/congenital anomalies

Agenesis of the ductus venosus and fetal growth restriction: Is there a relation? A tertiary care center experience and systematic review of the literature

An update on the antenatal diagnosis of agenesis of ductus venosus (ADV) by differentiating the various possible types of shunts, focusing on the associated fetal anomalies, and predicting neonatal outcomes. This study reviewed the experience of two tertiary referral centers and literature. An unfavorable outcome was detected in preterm fetuses (p = 0.017), fetuses with a genetic anomaly (p = 0.046) or other associated malformations (p < 0.001). 71% of ADVs with other anomalies had an extrahepatic ADV (p = 0.002). 76% of fetuses with Fetal Growth Restriction (FGR) had an extrahepatic ADV (p = 0.025). ADV may negatively influence fetal growth in cases with extrahepatic vein drainage.

Absence of Ductus Venosus: A Comparison of 2 Distinctive Fetal Autopsy Cases and Embryologic Perspectives

In fetal circulation, oxygenated blood from the placenta flows through the umbilical vein into the ductus venosus (DV), then enters the inferior vena cava, and subsequently reaches the right atrium of the heart. The DV serves as a shunt, allowing this oxygen-rich blood to bypass the liver. The absence of the DV (ADV), also known as agenesis of the DV, is a rare congenital anomaly. Without a DV, blood from the umbilical vein must follow alternative routes to the heart. In ADV cases, blood from the umbilical vein must follow 1 of 2 primary drainage patterns: either an extrahepatic shunt or an intrahepatic shunt. This report details the antenatal ultrasound and postmortem findings of 2 fetuses diagnosed with ADV by prenatal imaging studies. The first case involved a fetus with a persistent right umbilical vein connected directly to the suprahepatic IVC, accompanied by early obliteration of the left umbilical vein and true agenesis of the DV. This fetus also had additional congenital anomalies. In contrast, the second case involved a fetus with a normal left umbilical vein that entered the liver. However, despite an ultrasound diagnosis of "absence" of the DV, a DV was present, though markedly hypoplastic and probably minimally functional or non-functional. In this case, blood from the umbilical vein likely followed an alternate intrahepatic route through the portal and hepatic veins, before reaching the heart (intrahepatic shunt). These contrasting cases emphasize the heterogeneity of vascular anomalies and embryologic origins captured by the term "ADV." Additionally, the terminology of "absence" or "agenesis" may be misleading in some purported ADV cases. Specifically, in the second case, the DV was not absent; it was markedly hypoplastic instead. This also appears to be the first reported case of a hypoplastic DV in a fetus. Both cases underscore the importance of effective collaboration and clear communication between maternal-fetal medicine specialists and pathologists.

Ductus Venosus Agenesis and Portal System Anomalies-Association and Outcome

To evaluate the prenatal diagnosis of agenesis of ductus venosus (ADV) and portal venous system (PVS) anomalies and describe the outcome of these cases, either isolated or associated. We evaluated the intrahepatic vascular system regarding the presence of normal umbilical drainage and PVS characteristics in the second and third trimester of pregnancy. The associated anomalies and umbilical venous drainage were noted. Follow-up was performed at six months follow-up. Ultrasonography was performed in 3517 cases. A total of 19 cases were prenatally diagnosed: 18 ADV cases, seven abnormal PVS cases, and six associations of the two anomalies. We noted an incidence of 5.1‱ and 1.9‱ for ADV and PVS anomalies, respectively. Out of the 18 ADV cases, 27.7% were isolated. Five cases (26.3%) presented genetic anomalies. PVS anomalies were found in 33.3% of the ADV cases. ADV was present in 85.7% of the PVS anomalies. DV and PVS abnormalities were found with a higher than reported frequency. Normal DV is involved in the normal development of the PVS. Additional fetal anomalies are the best predictor for the outcome of ADV cases. Evaluation of PVS represents a powerful predictor for ADV cases and addresses the long-term prognosis.

Prenatal Diagnosis and Outcome of Umbilical–Portal–Systemic Venous Shunts: Experience of a Tertiary Center and Proposal for a New Complex Type

Aims: To share our experience in the prenatal diagnosis of umbilical–portal–systemic venous shunts (UPSVS) and to study the prognostic factors for proper prenatal and perinatal management. Material and Methods: A five-year prospective study regarding the detection of UPSVS was conducted in two referral centers, Medgin Ginecho Clinic and the Prenatal Diagnostic Unit of the tertiary center, University Emergency County Hospital Craiova, Romania. We included in the analysis a series of agenesis of ductus venosus (ADV) cases previously reported by our center. We analyzed the incidence of the UPSVS types, their associations, and outcome predictors. Results: UPSVS were diagnosed in all 16 cases that were presented to our center at the time of first trimester anomaly scan, except one (94.12%). We diagnosed: 19 type I (61.2%), 4 type II (12.9%) and 5 type IIIa (16.1%) UPSVS. In three cases (9.6%) we noted multiple shunts, which we referred to as type IV (a new UPSVS type). Type IIIa-associated fetal growth restriction (FGR) was found in 60% of cases. Major anomalies worsened the outcome. Of the UPVSS cases, 57.1% were associated with PVS anomalies. Genetic anomalies were present in 40% of the tested cases. Conclusions: The incidence of UPSVS in our study was 0.2%. Early detection is feasible. The postnatal outcome mainly depends on the presence of structural, genetic and PVS anomalies. FGR may be associated. The new category presented a poor outcome secondary to poor hemodynamic and major associated anomalies.

Identification of a New Variant of PUF60 Gene: Case Presentation and Literature Review

BACKGROUND/AIM

The aim of the study was to report the case of a 5-month-old boy with a complex prenatal and neonatal symptomatology diagnosed with a "de novo" pathogenic variant of PUF60 gene.

CASE REPORT

Our hospital, undertook the antenatal and postnatal care of a 27-year-old pregnant lady. This was her second baby with a previously healthy boy. During her routine first-trimester anomaly scan, increased nuchal translucency was noticed. Multiple anomalies were seen throughout her subsequent antenatal visits. This triggered a sequence of tests, examinations and differential diagnosis. The final diagnosis was made at 5 months postpartum following the result of the whole exome sequence, which described a variant of unknown clinical significance (VUS, class 3 variant) in the PUF60 gene. We are mindful that changing the classification of a variant of unknown significance is challenging and requires supporting and robust criteria. Considering clinical symptomatology produced by the pathogenic mutation in the PUF gene, the identified c.1640A>G variant may be categorized as likely pathogenic.

CONCLUSION

Our case adds new insights on the pathology and the underlying process involved in the PUF60 variant spectrum disorders. It also highlights the limits of current prenatal tests.

Prenatal diagnosis of an aberrant ductus venosus draining into the coronary sinus using two- and three-dimensional echocardiography: a case report

Background

Ductus venosus (DV) abnormalities may be associated with intracardiac or extracardiac deformities, chromosomal anomalies, and/or congestive heart failure. Aberrant DV connecting with the coronary sinus (CS) is rare and the prenatal diagnosis presents challenges for most examiners.

Case presentation

A 35-year-old pregnant woman, gravida 2, para 1, was referred to our center at 27 gestational weeks for a full evaluation of fetal cardiac anomalies. Transverse scans indicated normal cardiac anatomy except for a dilated CS; we then scanned sagittal planes to clarify the reasons for the CS dilatation. High-definition flow imaging (HDFI) together with radiant flow (R-flow) imaging was used to delineate the aberrant DV returning to the CS, enabling the diagnosis. Three-dimensional (3D) technology was also used to obtain color-rendered images showing the spatial relationships of the vessels involved, thus confirming the two-dimensional (2D) diagnosis. Chromosomal analysis revealed a normal karyotype. The neonate appeared healthy and the echocardiogram showed a normal cardiac anatomy except for a dilated CS with the DV closed and imperceptible.

Conclusions

The aberrant course of the DV returning to the CS was clearly demonstrable by traditional 2D echocardiography using HDFI and the R-flow technique. We deem it helpful to trace the inflow of the dilated CS to make the differential diagnosis. The 3D modality might also provide additional spatial information on the associated vessels and thereby assist in prenatal diagnosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-03870-x.

Prenatal features, associated co-morbidities and clinical course of agenesis of the ductus venosus in the current era

OBJECTIVES

Agenesis of the ductus venosus (ADV) has been associated with additional anomalies in up to 83% of cases. We sought to investigate characteristics, co-morbidities and outcomes of ADV in the current era. We hypothesized that rates of cardiac and non-cardiac diagnoses and survival would be higher, due to advances in genetic testing, prenatal diagnosis and surveillance.

METHODS

A retrospective series of cases diagnosed at our institution from 2007 to 2018 were identified by searching our database. Cardiac and obstetric charts were reviewed for cardiac and extra-cardiac anomalies, genetic results and outcomes.

RESULTS

Fourteen cases were diagnosed at a mean gestational age of 23.9 weeks (range 13-33). All had associated genetic, cardiac or extra-cardiac anomalies. Eight (57%) had cardiac anomalies and one other developed cardiomyopathy by 6 months. Extra-cardiac anomalies were present in 93% (13/14) and genetic diagnoses made in 75% (6/8) of those tested. Cardiac output Z-scores were >2 in 60% (6/10) prior to delivery. Two had hydrops, there was one intra-uterine death, 13 live-births and two neonatal deaths.

CONCLUSION

Our cohort had more associated diagnoses and a lower mortality than previously reported. In our experience, high output occurs frequently, however with a relatively low risk of hydrops and intrauterine death.

Ductus Venosus Agenesis as a Marker of Pallister-Killian Syndrome

The ductus venosus (DV) is a shunt that allows the direct flow of well-oxygenated blood from the umbilical vein (UV) to the coronary and cerebral circulation through the foramen ovale. Its agenesis has been associated with chromosomal abnormalities and rare genetic syndromes, structural defects, intrauterine growth restriction (IUGR) and even antepartum fetal demise. Pallister–Killian Syndrome (PKS) is a rare sporadic disorder with specific tissue mosaic distribution of an extra 12p isochromosome (i(12p)). Its main clinical features are moderate to severe intellectual disability/neuromotor delay, skin pigmentation abnormalities, typical facial appearance, variable association with multiple congenital malformations and epilepsy. Though prenatal findings (including congenital diaphragmatic hernia, ventriculomegaly, congenital heart disease, polyhydramnios, and rhizomelic shortening) have been described in literature, prenatal diagnosis is difficult as there are no associated identification signs no distinctive or pathognomonic signs, and some of these malformations are hard to identify prenatally. The tissue mosaicism linked to this syndrome and the decrease of the abnormal clone carrier of the i(p12) after successive trypsinizations of cultured cells makes the diagnosis even more challenging. We present the case of a 27.5 weeks pregnant woman with a fetal ductus venosus agenesis (DVA) as the main guide marker. To our knowledge this is the first case published in literature reporting a DVA as a guide sign to diagnose a complex condition as Pallister–Killian syndrome. We also underscore the key role of new genetic techniques as microarrays to avoid misdiagnosis when only a subtle sonographic sign is present in complex conditions like this.

Ductus venosus-systemic shunt. Report of six cases and systematic review of the literature

Objective: To evaluate the ultrasonographic features and pregnancy outcomes in women with ductus venosus-systemic shunt and systematic review of the literature.Method: A computerized search was conducted to identify cases of ductus venosus-systemic shunt between September 2016 and January 2018. Six patients were identified. Antenatal records and neonatal outcomes are presented. A systematic Embase, SCOPUS, and Medline search of published literature from 1991 to 2018 was performed using the terms "ductus venosus," "agenesis," "absence," "absent," "missing," "aberrant," and "variant."Results: Additional structural anomaly such as esophageal atresia with tracheoesophageal fistula was observed in one case. In other case, termination of pregnancy was performed due to Down syndrome. Other two of the six fetuses were monochorionic multiple pregnancies. In our review of the literature, additional anomalies were observed in 9 (42%) of the 21 cases.Conclusion: Our observation suggests that ductus venosus-systemic shunt can be associated with Down syndrome. Detailed examination should be performed to rule out additional abnormalities. Prognosis is good if the pathology is isolated.

Prenatal sonographic characteristics and postnatal outcomes of umbilical-portal-systemic venous shunts under the new in-utero classification: A retrospective study

An in-utero re-classification of umbilical-portal-systemic venous shunt (UPSVS) has recently been proposed. We retrospectively reviewed the sonograms of a large cohort of fetuses, identified and analyzed UPSVS cases, and presented the prenatal sonographic characteristics, birth outcomes, and follow-up results following the new classification system.Sonograms and clinical data of all participants who visited our departments from April 2016 to July 2018 were retrospectively reviewed. Identified cases of UPSVS were analyzed according to the new classification: Type I: umbilical-systemic shunt (USS); Type II: ductus venosus-systemic shunt (DVSS); Type IIIa: intrahepatic portal-systemic shunt (IHPSS) and Type IIIb: extrahepatic portal-systemic shunt (EHPSS). Postnatal follow-ups ranged from 3 months to 1 year.A total of 10 UPSVS cases were identified in 61,082 fetuses: 4 with Type I, 3 with Type II and 3 with Type IIIa. All 4 cases of USS had complete agenesis of the portal venous system, and had the umbilical vein drained into the inferior vena cava. Two USS cases also had trisomy 21. Pregnancy was terminated in all cases with a Type I shunt. Two fetuses with DVSS had normal portal venous system and were born full term. The pregnancy of 1 DVSS case was terminated due to the detection of trisomy 21. Three cases were IHPSS with full-term birth. One had chromosomal abnormality and 1 had surgery to repair the shunt 12-days post birth. In the 2 cases that did not receive repair surgery, sonographic examination revealed the portal-hepatic venous shunt was not closed at the 6-month follow-up period. However, the 1 case that had repair surgery appeared healthy at the 3-month follow-up period.UPSVS is extremely rare. Type I shunts have the poorest prognosis, and the presence of the intrahepatic portal venous system is key to live birth in UPSVS regardless of types. Chromosomal abnormalities and other organ anomalies can occur in any types of UPSVS. Therefore, karyotyping and examination of other organs should be performed once UPSVS is detected.

Ductus venosus agenesis and fetal malformations: what can we expect? - a systematic review of the literature

Background The ductus venosus agenesis (DVA) is a rare condition with a variable prognosis that relies partly on the presence of associated conditions. The purpose of our study was to analyze the literature regarding the post-natal outcome of fetuses with DVA associated with fetal malformations, in order to discuss the best management options for couples. Methods We performed a systematic review of the literature of MEDLINE and SCOPUS electronic databases in a 25-year period from 1992 to September 2017. Methods We found 340 cases of DVA associated with fetal abnormalities. The most common chromosomal abnormalities were: monosomy X (12/48, 25%), trisomy 21 (11/48, 22.9%) and trisomy 18 (6/48, 12.5%). From the 340 cases with DVA, in 31 cases the umbilical venous shunt type was not reported. Of the fetuses, 60.8% (188/309) had an extrahepatic umbilical venous drainage while 39.2% (121/309) presented an intrahepatic connection. The DVA was associated in 71 cases (23.0%) with cardiac abnormalities, in 82 cases (26.5%) with extracardiac abnormalities and in 85 cases (27.5%) with both cardiac and extracardiac abnormalities. Conclusion DVA associated with both cardiac and extracardiac malformations may confer a poorer fetal outcome, a clinically relevant fact that should clarify what can be expected from this entity and help prenatal counseling.

Predicting outcome in 259 fetuses with agenesis of ductus venosus - a multicenter experience and systematic review of the literature (.)

OBJECTIVE

To evaluate prenatal predictors of postnatal survival in fetuses with agenesis of ductus venosus (ADV).

METHODS

This retrospective study reviewed our experience and the literature between 1991 and 2015. Prenatal findings were evaluated and perinatal morbidity and mortality was documented.

RESULTS

A total of 259 cases were included in the present analysis from our centers and 49 published studies (15 patients from our retrospective cohort review and 244 from literature review). The intrahepatic and extrahepatic shunts were present in 32.0% (73/226) and 67.7% (153/226), respectively. Cardiomegaly (n = 64/259, 24.7%), hydrops (n = 31/259, 12.0%) and amniotic fluid abnormalities (n = 22/259, 8.5%) were among the most frequent initial ultrasound findings. One hundred and forty-seven fetuses (56.8%) had ADV without structural anomalies while 112 (43.2%) had associated anomalies (cardiac anomalies (n = 66), extra-cardiac anomalies (n = 19) and both cardiac and extra-cardiac anomalies (n = 27)). The mean gestational age (GA) at ultrasound diagnosis was 22.9 ± 6.9 weeks while the mean GA at delivery was 34 ± 7.5 weeks. The overall neonatal survival was 57.1% (n = 148/259). The following factors were associated with survival: advanced maternal age, earlier GA at diagnosis, prematurity, increased nuchal translucency, pericardial effusion, associated cardiac defects (especially AVSD), chromosomal abnormalities, hydrops, hygroma and limb anomalies.

CONCLUSION

Fetal hydrops, the presence of associated congenital anomalies and premature delivery are associated with poor prognosis in fetuses with ADV.

Agenesis of the venous duct: two cases of extrahepatic drainage of the umbilical vein and extrahepatic portosystemic shunt with a review of the literature

Agenesis of the venous duct is a rare congenital anomaly resulting in abnormal drainage of the umbilical vein into the foetal venous circulation. The clinical presentation and prognosis is variable, and may depend on the specific drainage pathways of the umbilical vein. We present two foetuses with agenesis of the venous duct, both associated with a postnatal portosystemic shunt, but with markedly different postnatal clinical courses. We also review all previously reported cases to better characterise this foetal disorder and the prognosis.

Umbilical vein insertion into the inferior vena cava: an ominous sign of chromosomal abnormalities?

This series describes the sonographic characteristics and pregnancy outcomes of fetuses with abnormal insertion of the umbilical vein (UV) into the inferior vena cava (IVC). We conducted a retrospective study that described the sonographic features of 6 patients who underwent a routine anatomic scan during early pregnancy. Six patients had a diagnosis of abnormal insertion of the UV to the IVC; in 3, the diagnosis was made at 12 weeks' gestation. Cardiac anomalies were detected in 3 patients, including ventricular septal defects, pericardial effusion, tricuspid and mitral regurgitation, and an aberrant right subclavian artery. Four had noncardiac anomalies, including cystic hygroma and skeletal, brain, and abdominal anomalies. Only 1 fetus who presented with UV insertion into the IVC as an isolated finding had a normal karyotype, resulting in term vaginal delivery. Four other patients had chromosomal abnormalities, including trisomies 13 and 21, Turner mosaicism of 45,XO/46,XY, and Robertsonian translocation, and 1 patient terminated the pregnancy without a karyotype evaluation. Abnormal insertion of the UV into the IVC with agenesis of the ductus venosus can be seen as early as the first trimester. When detected, a detailed anatomic examination should be performed, as well as a fetal karyotype evaluation. Isolated cases of insertion of the UV into the IVC at a position lower than usual may have a good prognosis.

Aberrant drainage of the umbilical vein into the coronary sinus without ductus venosus agenesis

We describe a case series of 4 fetuses with ectopic connections of the ductus venosus to the coronary sinus detected prospectively between August 2011 and February 2012 in 2 congenital cardiologic centers. An enlarged coronary sinus alerted the sonographer. Fetal echocardiography showed ectopic connection of the ductus venosus in an enlarged coronary sinus in all 4 cases. To our knowledge, this anatomic form of ectopic umbilical vein drainage has not previously been reported. The infants were doing well. This venous variant should be considered in cases of isolated coronary sinus dilatation after elimination of a left superior vena cava and a totally anomalous pulmonary vein connection.

Prenatal diagnosis of abnormal course of umbilical vein and ductus venosus agenesis: report of three cases

Ductus venosus connecting the portal and embryonic venous circulation into the inferior vena cava has a crucial role in fetal circulation. The absence of ductus venosus is a rare anomaly, in which the umbilical vein connection to the venous system may be extrahepatic, bypassing the liver or intrahepatic via the portal venous system. We report three cases of ductus venosus agenesis with associated anomalies. In two of them the connection was directly to the right atrium, whereas the umbilical vein drained to the left internal iliac artery in the third case.

Shunt diameter in agenesis of the ductus venosus with extrahepatic portosystemic shunt impacts on prognosis

OBJECTIVES

Agenesis of the ductus venosus (ADV) is a rare condition in which there are two variants of umbilical vein drainage: intrahepatic shunt or extrahepatic (portosystemic) shunt. It has been posited that the extrahepatic variant carries a poorer prognosis. However, in the absence of associated anomalies there is still a wide variation in outcome. We evaluated the portal system in cases of ADV and aimed to identify parameters that might predict outcome.

METHODS

We conducted a retrospective study of cases of ADV with extrahepatic shunt that had been examined in two centers, and collected new cases prospectively. The route of the shunt was depicted using two-dimensional (2D) and three-dimensional (3D) ultrasound imaging. In an attempt to characterize portal system and shunt developmental variations and their possible impact on outcome, the diameter of the shunt was compared with the diameter of the umbilical vein and the entire portal vasculature was assessed. Poor outcome was defined as persistent morbidity or fetal or neonatal death.

RESULTS

Twenty-two cases of ADV were identified: nine retrospectively and 13 prospectively. Aberrant shunts from the umbilical vein were identified to the right atrium, coronary sinus, inferior vena cava (IVC) and iliac vein. In seven of 22 cases (32%) a wide connection was observed. In six of these seven cases (86%) the outcome was poor, including four with severe associated anomalies and two with hepatic dysfunction. In five of these cases, cardiomegaly with tricuspid regurgitation was observed, as well as underdevelopment of the portal system. In only five of 15 cases with a narrow shunt (33%) was the outcome poor, and in all five cases the poor outcome was related to associated anomalies.

CONCLUSION

In cases of ADV with extrahepatic shunt, portal system development is impacted by the diameter of the shunt. If the shunt is narrow, the portal system will have developed normally. A wide shunt is associated with underdevelopment or absence of the portal system. In cases of ADV with extrahepatic shunt, prognosis is determined by the severity of associated anomalies, the diameter of the shunt and development of the portal system.

Isolated fetal intra-abdominal umbilical vein varix: clinical importance and recommendations

This series describes a single center's experience in follow-up and management of fetuses with an isolated fetal intra-abdominal umbilical vein varix. All cases with a fetal intra-abdominal umbilical vein varix that were diagnosed or referred to our medical center over 15 years were followed and managed. The definition of a fetal intra-abdominal umbilical vein varix used was a segment dilated to 9 mm or greater or at least 50% wider than the diameter of the adjacent umbilical vein. Over the 15-year period, our center had approximately 65,000 births with 28 cases of isolated fetal intra-abdominal umbilical vein varices: a prevalence rate of 1 case per 2300 births. Three of the 28 cases (10.7%) had intrauterine growth restriction. Five of 30 fetuses (17%) showed turbulent flow in the varix. We had no cases of intrauterine fetal death, and 27 of the 28 neonates had good outcomes. In contrary to earlier reports, we found that when a fetal intra-abdominal umbilical vein varix is isolated, a good fetal outcome is expected. On the basis of our experience, we have changed our policy and do not recommend inducing preterm labor. Nevertheless, close fetal surveillance until delivery is warranted.

The fetal venous system, Part II: ultrasound evaluation of the fetus with congenital venous system malformation or developing circulatory compromise

The human fetal venous system is well-recognized as a target for investigation in cases of circulatory compromise, and a broad spectrum of malformations affecting this system has been described. In Part I of this review, we described the normal embryology, anatomy and physiology of this system, essential to the understanding of structural anomalies and the sequential changes encountered in intrauterine growth restriction and other developmental disorders. In Part II we review the etiology and sonographic appearance of malformations of the human fetal venous system, discuss the pathophysiology of the system and describe venous Doppler investigation in the fetus with circulatory compromise.

Umbilical vein anomaly in fetuses with Down syndrome

OBJECTIVE

To describe the prevalence of abnormal umbilical vein (UV) anatomy in fetuses with Down syndrome.

METHODS

This was a retrospective survey covering a 24-month period of fetuses with a genetic diagnosis of Down syndrome following a routine early second-trimester (12-16-week) detailed fetal anomaly scan at a single academic tertiary referral center. In our unit this exam includes fetal umbilicoportal venous system evaluation.

RESULTS

During the study period, 37 fetuses were diagnosed with Down syndrome and had a detailed early anatomy scan. In four (11%) the detailed early anomaly scan revealed that the UV was connected to the hepatic portion of the inferior vena cava (IVC) at a position lower than its usual site. Their average gestational age at diagnosis was 13 + 6 (range, 11 + 6 to 15 + 2) weeks. Three of the four fetuses had a nuchal translucency thickness of 3-4 mm. In one fetus there was an additional finding of significant tricuspid regurgitation and the one with normal nuchal translucency thickness had an atrioventricular septal defect (atrioventricular canal) and umbilical cord hernia. During the same period three of 2500 (0.12%) fetuses with normal karyotype demonstrated similar anomalous insertion of the UV into the IVC, creating a portocaval shunt which had normal ductus venosus-like Doppler flow in all three cases. The odds ratio for abnormal umbilicoportal venous system in fetuses with Down syndrome compared with the normal population was 107.4 (95% CI, 19.2-637.1).

CONCLUSIONS

Fetuses with Down syndrome demonstrate an increased prevalence of abnormal connection of the UV to the IVC.

Prenatal diagnosis of congenital agenesis of the fetal portal venous system

OBJECTIVE

To describe the prenatal diagnosis and review our experience of fetal congenital agenesis of the portal venous system (CAPVS) and to review the current literature on this poorly documented vascular malformation.

METHODS

This was a retrospective survey covering the 12-year period between 1996 and 2008. The database of a single, large, ultrasonographic tertiary academic referral center in Israel was analyzed and cases with a prenatal diagnosis of CAPVS were identified. All fetuses underwent detailed biometric and structural ultrasound examinations and a precise anatomical description of the fetal umbilical, portal and hepatic venous system was noted, as well as the presence of aberrant vessels, shunt location and the presence or absence of the DV. Results of fetal echocardiography, karyotyping and toxoplasma, rubella, cytomegalovirus and herpes evaluations were determined. Medical records were evaluated. Diagnosis was confirmed by pathology, postmortem venography or neonatal ultrasound or venography. Liveborns were examined by a certified neonatologist and long-term follow-up from pediatric gastroenterology units was determined.

RESULTS

Nine cases with CAPVS were studied. In all cases an aberrant umbilical-portal vein was the primary indication for detailed portal system evaluation. Five fetuses demonstrated total CAPVS (Type I) and four showed partial agenesis of the portal vein (Type II). Among the five Type I fetuses, there was a shunt from the umbilical vein to the inferior vena cava in three (60%), to the right atrium in one and to the coronary sinus in one. In this group, in only one case could we delineate a common confluence between the splenic vein and the superior mesenteric vein shunting to the inferior vena cava. In four cases termination of pregnancy was performed due to additional findings: one case with hydrothorax, ascites and mitral atresia, one with cleft lip/palate and one with trisomy 21. One case had no additional anomalies, but the parents elected to terminate the pregnancy. All four of the Type II fetuses had a portosystemic shunt: in two cases to the right atrium, in one to the iliac vein and in one to the right hepatic vein. In three, the shunt resolved spontaneously. In only one case was abnormal liver function present over a follow-up period of 2-10 years.

CONCLUSION

CAPVS can be detected prenatally. An abnormal course of the umbilical vein necessitates prompt sonographic evaluation of the umbilical-portal venous system and meticulous investigation for additional anomalies. Complete CAPVS may be associated with remote clinical consequences of which the parents should be informed. Partial CAPVS has a favorable prognosis.

Reversed end-diastolic flow in the umbilical artery at 10-14 weeks of gestation is associated with absent pulmonary valve syndrome

OBJECTIVE

To determine the incidence of reversed end-diastolic flow (REDF) in the umbilical artery in high-risk first-trimester pregnancies and evaluate associated conditions.

METHODS

This was a prospective evaluation of the umbilical artery Doppler waveforms of 614 consecutive high-risk pregnancies between 10 and 14 weeks of gestation, to determine those with REDF. The associated anomalies and characteristics of these fetuses were then investigated.

RESULTS

In 278/614 (45.3%) fetuses, there was positive end-diastolic flow in the umbilical artery; in 331/614 (53.9%) end-diastolic flow was absent and in 5/614 (0.8%) there was REDF. Three of the five fetuses with REDF had tetralogy of Fallot (TOF) with absent pulmonary valve syndrome (APVS) and a patent ductus arteriosus, and all three showed signs of cardiac failure, with reversed blood flow in the ductus venosus during atrial systole and generalized skin edema. Another fetus had a large ventricular septal defect and the remaining fetus had agenesis of the ductus venosus. Three fetuses had trisomy 18 and one had trisomy 13.

CONCLUSIONS

REDF in the umbilical artery is very rare in early pregnancy and mostly occurs in association with major fetal vascular anomalies and cardiac defects, particularly TOF with APVS and patent arterial duct. We propose that the patency of the arterial duct in TOF with APVS leads to heart failure with subsequent demise early in pregnancy. Therefore, the frequent absence of the arterial duct observed in APVS in later pregnancy is more likely to be a result of early selection than a prerequisite for the development of this lesion as has been proposed previously.

Diagnosis of absent ductus venosus in a population referred for fetal echocardiography: association with a persistent portosystemic shunt requiring postnatal device occlusion

OBJECTIVE

The purpose of this series was to assess the incidence, anatomic variants, and implications of an absent ductus venosus (ADV) in patients referred for fetal echocardiography.

METHODS

We searched our fetal cardiology database for diagnoses of ADV from May 2003 to December 2006.

RESULTS

During the study period, we performed 1328 fetal echocardiographic examinations in 990 fetuses. We found 6 cases of ADV (6/1000). Indications for fetal echocardiography were cardiomegaly, dilated umbilical or systemic veins, and extracardiac abnormalities. We identified 5 anatomic variants of ADV. In 2 patients, the umbilical vein connected to the systemic venous circulation by way of the portal sinus: via an abnormal venous channel from the portal sinus to the right atrium (case 1) and presumably via hepatic sinusoids to the hepatic veins (case 2). In the remaining 4 patients, the umbilical vein bypassed the portal sinus and the liver and connected to the systemic venous circulation via an abnormal venous channel: from the umbilical vein to the right atrium (case 3), from the umbilical vein to the inferior vena cava (cases 4 and 5), and from the umbilical vein to the right iliac vein (case 6). All patients survived; 2 required cardiovascular intervention. No intervention was required in 3 patients.

CONCLUSIONS

An ADV should be ruled out in a fetus with unexplained cardiomegaly or dilatation of the umbilical vein, systemic veins, or portal sinus. To our knowledge, prenatal diagnosis of an ADV with an abnormal communication between the portal sinus and the right atrium has not been reported previously. The portosystemic communication persisted after birth and required device occlusion.

Cardiac anomalies in the setting of the Abernethy malformation of the portal vein

We describe a child with tricuspid atresia associated with a porto-systemic shunt and complete absence of the portal vein, the latter known as the Abernethy malformation. As far as we are aware, this association has not previously been reported. We review the various cardiac defects that have been reported in children with the Abernethy malformation, emphasizing the interesting clinical presentations of this rare malformation of the portal venous system.

Absence of ductus venosus-importance of umbilical venous drainage site

OBJECTIVE

To evaluate the conditions associated with absent ductus venosus (ADV) diagnosed by prenatal ultrasonography.

METHODS

Retrospective review of 23 cases with ADV diagnosed in two tertiary referral centers with a general screening policy concerning Doppler assessment of the ductus venosus. The results are discussed together with 63 cases from a review of the literature.

RESULTS

In 19 fetuses the umbilical vein connected to the portal sinus, while the remaining four fetuses had extrahepatic umbilical venous drainage. Associated anomalies were present in 15 out of 23 fetuses: complex malformation syndromes (n = 6), chromosomal anomalies (n = 4), isolated cardiac defects (n = 4) and isolated extracardiac anomalies (n = 1). Eight fetuses had either no associated anomalies or minor anomalies. Hydropic changes were present in 12 of the 23 fetuses. In common with the reviewed cases, the presence of cardiac malformations, complex non-chromosomal malformation syndromes and hydrops was significantly associated with intrauterine or postnatal death while the type of umbilical venous drainage was not significantly different between survivors and non-survivors. However, among fetuses with no or minor associated anomalies the outcome was significantly better in the group without liver bypass.

CONCLUSIONS

ADV is significantly associated with fetal cardiac and extracardiac anomalies, aneuploidies and hydrops. Fetuses with liver bypass have an additional risk of developing congestive heart failure that significantly affects outcome, even if the fetal cardiovascular anatomy is otherwise normal. ADV without liver bypass seems to have a more favorable prognosis if it is not associated with other malformations.

Physiology of the fetal circulation

Our understanding of fetal circulatory physiology is based on experimental animal data, and this continues to be an important source of new insight into developmental mechanisms. A growing number of human studies have investigated the human physiology, with results that are similar but not identical to those from animal studies. It is time to appreciate these differences and base more of our clinical approach on human physiology. Accordingly, the present review focuses on distributional patterns and adaptational mechanisms that were mainly discovered by human studies. These include cardiac output, pulmonary and placental circulation, fetal brain and liver, venous return to the heart, and the fetal shunts (ductus venosus, foramen ovale and ductus arteriosus). Placental compromise induces a set of adaptational and compensational mechanisms reflecting the plasticity of the developing circulation, with both short- and long-term implications. Some of these aspects have become part of the clinical physiology of today with consequences for surveillance and treatment.

Fetal intra-abdominal umbilical vein varix: what is the clinical significance?

OBJECTIVE

To assess the clinical significance of fetal intra-abdominal umbilical vein (FIUV) varix.

METHODS

We reviewed all cases of FIUV varix diagnosed in a university hospital from 1994 to 2003 and searched the English literature for cases of prenatal diagnosis of FIUV varix. The FIUV was considered dilated when the measurements were above 2 SD of the mean for gestational age. Cases reported in the literature were included if they met the diagnostic criteria for FIUV varix.

RESULTS

Between 1994 and 2003, 13 fetuses were diagnosed in our hospital as having FIUV varix. Review of the literature revealed an additional 80 cases. Fetal outcome was available for analysis in 91 cases. Additional sonographic abnormalities were detected prenatally in 29 cases (31.9%), most commonly anomalies of the cardiovascular system (including structural and functional abnormalities), hydropic features and anemia. There were nine (9.9%) cases of chromosomal abnormalities. All except one had associated sonographic abnormalities. There were 12 (13%) perinatal losses. Only 54 cases (59.3%) of fetuses with FIUV varix had a normal obstetric outcome. In the 62 cases with isolated FIUV varix, there were five unexplained intrauterine deaths (8.1%) occurring between 29 and 38 weeks of gestation. The incidence of complications, which included intrauterine death, thrombosis of the umbilical vein and abnormal antenatal cardiotocogram, were significantly higher (P = 0.01, Fisher's exact test) if the diagnosis of FIUV varix was made before 26 weeks.

CONCLUSIONS

FIUV varix is associated with a high incidence of fetal anomalies and obstetric complications. Detailed sonography is necessary to exclude fetal anomalies. Karyotyping should be offered when additional fetal abnormalities are detected. Intensive surveillance including color Doppler ultrasound should be started from the moment of diagnosis until delivery, especially in those cases presenting early in pregnancy.

Prenatal diagnosis of umbilicoportosystemic shunts: report of 11 cases and review of the literature

OBJECTIVE

The objective of our study was to classify, understand, and illustrate abnormalities of the embryologic development of the umbilical vein and the portal system resulting in umbilicoportosystemic shunts. According to our data and a review of the literature, we propose an anatomic, biometric, and hemodynamic assessment of umbilicoportosystemic shunts.

CONCLUSION

Umbilicoportosystemic shunts encompass different congenital vascular abnormalities that should be recognized because they may interfere with fetal growth and circulation.

Anomalies of the Fetal Venous System: A Report of 26 Cases and Review of the Literature

OBJECTIVE

To evaluate sonographic appearance, natural history, and neonatal outcome of fetal venous anomalies.

METHODS

We performed an observational study, including all fetuses affected by abnormalities of the venous system diagnosed by ultrasound during the prenatal period.

RESULTS

26 fetuses were identified. Other malformations were present in 5 cases (19.2%), 1 fetus had trisomy 21, and 1 fetus had intrauterine growth retardation (IUGR). Twenty-five pregnancies ended in liveborn infants, and there was 1 case of unexplained intrauterine death in the fetus with IUGR affected by varix of the umbilical vein.

CONCLUSIONS

Fetal venous anomalies are very rare and may be associated with fetal malformations or IUGR. Conservative management appears to be an adequate medical practice in the absence of other fetal problems, but in the presence of a varix of the umbilical vein, serial follow-up scans are needed to exclude the onset of hydrops or thrombosis of the varix.

The fetal circulation

Accumulating data on the human fetal circulation shows the similarity to the experimental animal physiology, but with important differences. The human fetus seems to circulate less blood through the placenta, shunt less through the ductus venosus and foramen ovale, but direct more blood through the lungs than the fetal sheep. However, there are substantial individual variations and the pattern changes with gestational age. The normalised umbilical blood flow decreases with gestational age, and, at 28 to 32 weeks, a new level of development seems to be reached. At this stage, the shunting through the ductus venosus and the foramen ovale reaches a minimum, and the flow through the lungs a maximum. The ductus venosus and foramen ovale are functionally closely related and represent an important distributional unit for the venous return. The left portal branch represents a venous watershed, and, similarly, the isthmus aorta an arterial watershed. Thus, the fetal central circulation is a very flexible and adaptive circulatory system. The responses to increased afterload, hypoxaemia and acidaemia in the human fetus are equivalent to those found in animal studies: increased ductus venosus and foramen ovale shunting, increased impedance in the lungs, reduced impedance in the brain, increasingly reversed flow in the aortic isthmus and a more prominent coronary blood flow.

Three-dimensional color power imaging of the fetal hepatic circulation

OBJECTIVE

The purpose of this study was to describe the use of three-dimensional power Doppler ultrasonography to identify vascular congenital anomalies of fetal portosystemic and umbilical venous systems.

STUDY DESIGN

In a prospective study, the hepatic and umbilical venous systems were examined in 390 fetuses with two-dimensional ultrasonography, color, and spectral Doppler imaging. Fetuses suspected to have anomalies of the portal system and ductus venosus were additionally examined with three-dimensional power Doppler ultrasonography.

RESULTS

Vascular anomalies were identified in 8 fetuses (absent ductus venosus, n=4; direct connection between the umbilical vein and the right atrium, n=2; and direct connection between the umbilical vein and the inferior vena cava, n=2) out of the 310 in which the venous system could be adequately imaged (prevalence=2.6%). Three-dimensional power Doppler imaging showed the course of the umbilical vein, its relationship to the portosystemic circulation, and whether a ductus venosus was present.

CONCLUSION

Three-dimensional power Doppler ultrasonography can be used to image normal fetal hepatic and portal circulation, as well as identify anomalies of the fetal portosystemic and umbilical venous systems.

Absent or hypoplastic thymus on ultrasound: a marker for deletion 22q11.2 in fetal cardiac defects

OBJECTIVE

Congenital heart defects (CHD), particularly conotruncal anomalies, may be associated with deletion of chromosome 22q11.2. Thymic aplasia or hypoplasia is known to be a typical feature in this condition. We aimed to establish (i) the prevalence of del22q11.2 in fetal CHD and (ii) whether ultrasound assessment of an absent or hypoplastic fetal thymus helps in preselection of a group who are at high risk for this deletion.

STUDY DESIGN

In fetuses (> 16 weeks) with CHD, karyotyping and fluorescence in situ hybridization for 22q11.2 were offered and the fetal thymus was evaluated sonographically.

RESULTS

One hundred and forty-nine fetuses with CHD and normal karyotype were analyzed. Seventy-six fetuses had conotruncal anomalies. 22q11.2 deletion was present in 10 cases (6.7%), all of which had conotruncal anomalies (13.1%). Thymic hypoplasia or absence was suspected in 11 cases with conotruncal anomaly. Nine of these 11 had the deletion; two cases were false positive. One fetus with a normal-sized thymus had deletion of 22q11.2 (sensitivity 90%, specificity 98.5%, positive predictive value 81.8%, and negative predictive value 99.2%). By subtype of cardiac anomaly, there was deletion in four of six fetuses with interruption of the aortic arch, two of four with absent pulmonary valve syndrome, three of nine with truncus arteriosus and one of 11 cases of tetralogy of Fallot. Pulmonary atresia with ventricular septal defect (n = 7), right-sided aortic arch (n = 4), transposition of the great arteries (n = 14), double outlet right ventricle (n = 13) and other complex malpositions of the great vessels (n = 8) were not associated with the deletion.

CONCLUSION

Thymic hypoplasia or aplasia may reliably be diagnosed during fetal echocardiography. The technique allows identification of a group at high risk for 22q11.2 deletion and is more specific and sensitive than by subtype of cardiac anomaly alone.