Left Superior Vena Cava in the Fetus: A Rarely Isolated Anomaly

Association of Prenatally Diagnosed Isolated Single Left Superior Vena Cava and Postnatal Development of Coarctation of the Aorta

To report the prevalence of coarctation of the aorta (CoA) in fetuses with single left superior vena cava (SL-SVC) and to evaluate changes in echocardiographic measurements. Additionally, to report the prevalence of associated malformations. Retrospective observational study of fetuses diagnosed with SL-SVC between 2012 and 2021 at a tertiary fetal cardiology unit. In fetuses without intracardiac abnormalities, Z-scores of the ventricles, great arteries, and Doppler flow patterns are reported. We identified 47 fetuses with SL-SVC of which 8/47 (17%) had abnormal intracardiac anatomy. One fetus was lost to follow-up. Of those with normal intracardiac anatomy and postnatal follow-up (38), karyotype abnormalities were confirmed in 2/38 (5%) and ECA in 8/38 (21%). 33/38 were live-born. None developed CoA postnatally. Paired analysis of Z-scores between early and late scans of 24 fetuses showed that diameters of the right heart structures and Doppler flows of tricuspid valve increased significantly during pregnancy, while the left heart structures and flow patterns did not change. The median risk of CoA did not change between the early and the late scan. We did not observe CoA in this cohort. A degree of ventricular asymmetry was present, but this was due to right heart dominance rather than hypoplasia of left heart structures. This likely reflects redistribution of blood and does not appear to confer increased risk of CoA. Predictive models of the postnatal development of CoA which set the dimensions of right and left heart structures in relation might not be applicable in this situation.

Persistant Left Superior Vena Cava with and Without Right Superior Vena Cava: Significance of Prenatal Diagnosis

This study aims to define the associated anomalies with PLSVC, and to compare single PLSVC and bilateral superior vena cava in terms of accompanying anomalies and pregnancy outcomes. This was a retrospective study of the fetuses diagnosed with single and/or bilateral SVC at a tertiary fetal medicine center during 8 years. We detected 16 cases of single PLSVC and 84 cases of bilateral SVC. We found an association between the PLSVC and cardiac and extracardiac anomalies. Comparison between single PLSVC and BSVC cases revealed significant differences in the occurrence of heterotaxy and right isomerism. The study highlights the importance of prenatal diagnosis in PLSVC cases. Isolated PLSVC with situs solitus may be considered a benign finding, but larger studies are needed to understand the clinical implications of PLSVC in relation to chromosomal anomalies. Routine screening protocols should include three-vessel and trachea views to detect PLSVC.

Single left superior vena cava: antenatal diagnosis, associated anomalies and outcomes

OBJECTIVES

To describe the associated cardiac and extracardiac findings and estimate the prevalence of single left superior vena cava (LSVC) among fetuses referred for fetal echocardiography.

METHODS

This was a retrospective case series of fetuses diagnosed with situs solitus and single LSVC at the Brompton Centre for Fetal Cardiology, London, UK, from October 2006 to December 2020. Prenatal and postnatal outcome data were collected. Prenatal diagnosis was based on abnormal vessel alignment at the three-vessel view and/or three-vessel-and-trachea view, showing a vessel to the left of the pulmonary artery (i.e. the LSVC) and absence of the usual vessel to the right of the ascending aorta (i.e. the right superior vena cava), and further visualization of the LSVC draining into the coronary sinus.

RESULTS

Of 19 968 fetal echocardiograms performed during the study period, 34 cases of single LSVC were identified (a prevalence of 0.17%). Of these, 32 pregnancies had a live birth, one was lost to follow-up and one resulted in intrauterine demise. Single LSVC was isolated in 79.4% of cases. No major congenital heart disease was identified. One fetus showed mild isthmus hypoplasia, with no aortic coarctation postnatally. Two fetuses had umbilical vessel abnormalities. A genetic abnormality was found in one case (15q24.1-q24.2 deletion).

CONCLUSIONS

Antenatal diagnosis of single LSVC in the setting of situs solitus is usually a benign isolated finding. Nevertheless, investigation of other cardiac, extracardiac and genetic disorders should be considered. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Persistent Left Superior Vena Cava Significance in Prenatal Diagnosis—Case Series

The persistent left superior vena cava (PLSVC) is a congenital heart anomaly reported in 0.3–0.5% of the general population and can be associated with congenital heart diseases in up to 8% of cases. Prenatal identification of PLSVC is important to prompt an extended cardiac and extracardiac fetal examination. We retrospectively reevaluated anomaly scans performed in our unit in a 2-year interval according to the national guidelines to evaluate the incidence of PLSVC and its association with prenatal morbidity. In our population, the incidence of PLSVC was 0.31%, and we found a low association with cardiac and extracardiac anomalies. The standard sections (three-vessel and trachea view, four-chamber view and outflow tract’s view) are insufficient to exclude cardiac anomalies whenever PLSVC is found. In our case series, only one newborn required postnatal surgery for total pulmonary vein anomaly, and at 2 years of life all babies had a normal evolution. Prenatal diagnosis of PLSVC can raise counseling issues; therefore, awareness of its good outcome when isolated and need for an extended examination to rule out other anomalies is very important.

Chromosomal Microarray Analysis in Fetuses Detected with Isolated Cardiovascular Malformation: A Multicenter Study, Systematic Review of the Literature and Meta-Analysis

Cardiovascular malformations (CVM) represent the most common structural anomalies, occurring in 0.7% of live births. The CVM prenatal suspicion should prompt an accurate investigation with fetal echocardiography and the assessment through genetic counseling and testing. In particular, chromosomal microarray analysis (CMA) allows the identification of copy number variations. We performed a systematic review and meta-analysis of the literature, studying the incremental diagnostic yield of CMA in fetal isolated CVM, scoring yields for each category of heart disease, with the aim of guiding genetic counseling and prenatal management. At the same time, we report 59 fetuses with isolated CVM with normal karyotype who underwent CMA. The incremental CMA diagnostic yield in fetuses with isolated CVM was 5.79% (CI 5.54–6.04), with conotruncal malformations showing the higher detection rate (15.93%). The yields for ventricular septal defects and aberrant right subclavian artery were the lowest (2.64% and 0.66%). Other CVM ranged from 4.42% to 6.67%. In the retrospective cohort, the diagnostic yield was consistent with literature data, with an overall CMA diagnostic yield of 3.38%. CMA in the prenatal setting was confirmed as a valuable tool for investigating the causes of fetal cardiovascular malformations.

Prenatal persistent left superior vena cava in low population: Not a benign vascular anomaly

OBJECTIVE

The aim of this study is to identify prenatally diagnosed cases of persistent left superior vena cava (PLSVC) in our clinic, to evaluate the associated structural and chromosomal results, and to review their outcome.

MATERIALS AND METHODS

During a four-year period, patients with fetal PLSVC were detected by echocardiography. We reviewed medical records of these affected pregnancies, including maternal demographics, sonographic findings, chromosomal microarray results and pregnancy outcomes.

RESULTS

There were a total of 140 cases of fetal PLSVC. Eighty-nine fetuses (63.6%) had associated structural anomalies, while the remaining 51 fetuses (36.3%) had PLSVC as an isolated finding. In the non-isolated cases, cardiac anomalies were present in 72 fetuses (80.9%), and extracardiac abnormalities in 45 fetuses (50.6%). Among the 89 cases with non-isolated PLSVC, 12 cases had chromosomal abnormalities including 5 cases of aneuploidies. Among the 51 cases with isolated PLSVC, one pregnancy of chromosomal microduplication was detected.

CONCLUSION

Isolated PLSVC is a benign vascular anomaly in low risk population. However, the information about background risk of identifying an abnormal clinically significant CMA result should be conveyed to all pregnant women when they consults this vascular variation.

The Additional Role of the 3-Vessels and Trachea View in Screening for Congenital Heart Disease

Background and Objectives: Although frequent and associated with high mortality and morbidity rate, congenital heart disease (CHD) has a suboptimal prenatal detection rate, with significant variation according to the scanning protocol. The aim of this study was to evaluate the role of the 3-vessels and trachea view (3VT) in detecting CHD, with or without the use of Color Doppler, with an emphasis on major CHD. Materials and Methods: We performed a retrospective study on 1596 unselected pregnant patients presenting at 11–37 weeks of gestation for a routine anomaly scan. We selected all CHD cases, and we analyzed the performance of the 4-chamber (4C) and 3VT view in detecting CHD. Results: A total of 46 fetuses with CHD were identified, yielding a 2.86% overall incidence, and 0.87% for major CHD. Grayscale 4C detected 47.8% of all CHD, going up to 71.7% by adding grayscale 3VT, with no major CHD remaining undetected by combining grayscale 4C and 3VT. Conclusions: Grayscale 4C and 3VT views are effective in detecting major CHD, thus proving their utility even in a low resource setting.

Clinical significance of prenatally diagnosed persistent left superior vena cava

AIMS

The aim of our study was to investigate the persistent left superior vena cava (PLSVC) cases diagnosed in the prenatal period in our clinic and to compare the obstetric and genetic outcomes of isolated PLSVC cases with cases accompanied by other cardiac or extracardiac anomalies.

METHODS

The cases diagnosed as PLSVC between January 2015 and January 2019 in our perinatology clinic were evaluated retrospectively. Patients were divided into two subgroups as isolated PLSVC and PLSVC accompanied by another anomaly. Furthermore, patients with extra anomalies were divided into three groups which are cardiac anomaly, extracardiac anomaly and those with both. The groups were compared in terms of genetic results and obstetric outcomes.

RESULTS

89 patients were included in our study. Cases with positive pregnancy outcomes were significantly higher in the isolated PLSVC group than with extra anomaly group (p<0.001). No karyotype anomaly was observed in the isolated group. Pregnancy results were significantly worse (postpartum demise, termination of pregnancy, in utero demise) in with both cardiac and extracardiac anomalies group (p<0.001). There was no significant difference between the groups in terms of karyotype results (p=0.535).

CONCLUSION

The diagnosis of PLSVC has gained importance and it can be made easier due to the fact that anatomic imaging can be performed in more detail. The isolated PLSVC cases have a very good prognosis. Obstetric outcomes vary according to the accompanying anomaly.

Gradual diagnosis and clinical importance of prenatally detected persistent left superior vena cava with absent right superior vena cava - a case report and literature review

Persistent left superior vena cava is a malformation of cardinal veins. We report a case of a secundigravida who had many fetal ultrasound examinations – first performed by an obstetrician (who described fetal mediastinum as “abnormal”), second by other obstetrician, who performed basic fetal echocardiographic examination and diagnosed persistent left superior vena cava. The woman was referred to a tertiary center for detailed fetal echocardiography. The diagnosis of persistent left superior vena cava with agenesis of the right superior vena cava was confirmed. The anomaly had no influence on fetal hemodynamic stability, fetal life, delivery and early postnatal period. After delivery, the neonate was under observation for further anomalies, aortic coarctation in particular. Prenatal and postnatal management was summarized. Literature review is presented.