Fetal Vascular Rings and Pulmonary Slings: Strategies for Two- and Three-Dimensional Echocardiographic Diagnosis

Three- and Four-Dimensional Imaging of Ductus Arteriosus in Fetuses With Pulmonary Atresia and Aortic Arch Abnormalities

Advances in fetal echocardiography including newer techniques like 4D spatio-temporal image correlation technology has improved our understanding of fetal cardiac and extracardiac abnormalities. High resolution ultrasound combined with color Doppler and 3D rendering have contributed to an improved understanding of the fetal vascular system and its anomalies. This pictorial essay including ultrasound images and videos alongside their respective clay models, provides precise information of duct anatomy in fetuses with pulmonary atresia and aortic arch abnormalities.

Confusion from prenatal diagnosis: Type C persistent fifth aortic arch or right-side ductus arteriosus

We described a case of a double aortic arch (DAA) with a subaortic left brachiocephalic vein (LBCV) and right-side ductus arteriosus using high-definition (HD) flow render mode and spatiotemporal image correlation (STIC). We experienced uncertainty regarding this interesting case despite the diagnosis of right-sided ductus arteriosus. The ductus arteriosus originates from the right pulmonary artery (PA) and converges into the descending aorta (DAO), whereas the vessel originated from the PA and converged into the ascending aorta (AAO). Therefore, we assumed that the vessel connecting the PA to AAO may be a type-C persistent fifth aortic arch (PFAA).

Vascular ring: prenatal diagnosis and prognostic management based on sequential cross-sectional scanning by ultrasound

BACKGROUND

In terms of embryonic origin, vascular ring is a congenital anomaly in which the aortic arch and its branches completely or incompletely encircle and compress the trachea or esophagus. Early and accurate diagnosis of a vascular ring is the key to treatment. Prenatal diagnosis mainly relies on fetal echocardiography, but the rate of missed diagnosis and misdiagnosis is still very high, and the prognosis has not been evaluated. The aim of this study was to investigate the accuracy of prenatal diagnosis and to evaluate the prognosis semi-quantitatively according to the shape of the ring and the distance between the vessel and the trachea.

METHODS

From 2019 to 2021, 37,875 fetuses underwent prenatal ultrasound examination in our center. All fetal cardiac examinations were performed using the fetal echocardiography method proposed by the American Institute of Ultrasound in Medicine (AIUM) combined with dynamic sequential cross-sectional observation (SCS). For SCS, the standard abdominal section was taken as the initial section, and the probe was moved cephalically along the long axis of the body until the superior mediastinum had disappeared. If a vascular ring was found, the shape of the ring and the distance of the branch to the airway were observed. The distance relationship with the airway was divided into three grades: I-III; the closer the distance, the lower the grade. The vascular rings were monitored every 4 weeks before birth. All were monitored before surgery or 1 year after birth.

RESULTS

A total of 418 cases of vascular rings were detected. There was no missed diagnoses or misdiagnoses by SCS. The vessels formed different shaped rings according to their origin and route. Grade I, "" and "O" rings have a poor prognosis and are associated with the highest risk of respiratory symptoms.

CONCLUSIONS

SCS can accurately diagnose vascular rings before delivery, evaluate the shape and size of the rings to conduct prenatal monitoring of children until birth, which plays a guiding role in airway compression after birth.

Application of Color Doppler with 3- and 4-Dimensional Ultrasonography in the Prenatal Evaluation of Fetal Extracardiac and Placental Abnormalities

Using color Doppler flow imaging or high-definition flow imaging with three-dimensional volume or spatio-temporal image correlation (STIC) in the glass-body mode allows displaying both gray-scale and color information of the heart cycle-related flow events and vessel spatial relationship. Conventionally, STIC in the glass-body mode has been used to examine the fetal heart and assess heart defects. Recently, a novel application of STIC in the visualization of abdominal precordial veins and intraplacental vascularization in singleton pregnancies has been reported. The aim of this present review is to discuss the use of color Doppler with three- and four-dimensional ultrasonography in the evaluation of extracardiac, placental, umbilical cord and twin abnormalities with examples. The glass-body mode is complementary to conventional 2D ultrasonography. Further studies are required to investigate use of the glass-body mode in the assessment of intraplacental vascularization in singleton and twin pregnancies.

3D Approaches in Complex CHD: Where Are We? Funny Printing and Beautiful Images, or a Useful Tool?

Echocardiography, CT and MRI have a crucial role in the management of congenital heart disease (CHD) patients. All of these modalities can be presented in a 2D or a 3D rendered format. The aim of this paper is to review the key advantages and potential limitations, as well as the future challenges of a 3D approach in each imaging modality. The focus of this review is on anatomic rather than functional assessment. Conventional 2D echocardiography presents limitations when imaging complex lesions, whereas 3D imaging depicts the anatomy in all dimensions. CT and MRI can visualise extracardiac vasculature and guide complex biventricular repair. Three-dimensional printed models can be used in depicting complex intracardiac relationships and defining the surgical strategy in specific lesions. Extended reality imaging retained dynamic cardiac motion holds great potential for planning surgical and catheter procedures. Overall, the use of 3D imaging has resulted in a better understanding of anatomy, with a direct impact on the surgical and catheter approach, particularly in more complex cases.

Prenatal Diagnosis of Pulmonary Atresia With Ventricular Septal Defect and an Aberrant Ductus Arteriosus in a Dextrocardia by Two- and Three-Dimensional Echocardiography: A Case Report

Introduction

Prenatal diagnosis of pulmonary atresia is difficult in relative, especially when the pulmonary artery is slim and hypoplastic in development. It is of great importance to search for the blood supply to the pulmonary artery in those fetuses while it challenges most screening sonographers, even fetal echocardiography specialists. We herein report a rare case of pulmonary atresia with ventricular septal defect, complicated with an aberrant ductus arteriosus which provides the blood supply to the pulmonary artery. Besides, the case was also accompanied by cardiac malposition, dextrocardia with situs solitus. The echocardiographic characteristics and autopsy findings are also presented to approach the skill of fetal diagnosis.

Case presentation

A 30-year-old primigravida woman was referred to our center at gestational age of (24 ± 3) weeks for further fetal cardiac examination for suspected fetal cardiac anomalies. Fetal echocardiography revealed dextrocardia, situs solitus of the atria, an L-ventricular loop, a ventricular septal defect, an enlarged coronary sinus, and pulmonary atresia by transverse scanning. The ductus arteriosus was not present at the three-vessel trachea view with the retrograde flow showing in the pulmonary artery trunk, which suggested the possibility of an aberrant ductus arteriosus. Sagittal and coronal scanning was attempted to find that the pulmonary artery connected with the innominate artery via the aberrant ductus arteriosus. Three-dimensional echocardiography with spatio-temporal image correlation and high-definition flow imaging technique was performed to obtain the three-dimensional rendered image, which clearly showed the malformation in space. The pregnancy was terminated and the gross findings confirmed the prenatal diagnosis.

Conclusion

A detailed evaluation of fetal cardiac anatomy and hemodynamics is crucial for the detection of an aberrant ductus arteriosus, which plays an important role in the diagnosis of pulmonary atresia with ventricular septal defect. Sagittal and coronal scanning is useful to find the course of this aberrant ductus arteriosus. The three-dimensional echocardiography with spatio-temporal image correlation technique could provide additional spatial information to show great arteries in detail, which can serve as a supplement to traditional two-dimensional modality and benefit examiners to make an accurate diagnosis.

Fetal echocardiographic markers to differentiate between a right and double aortic arch

OBJECTIVES

To describe the fetal echocardiographic features of a double aortic arch (DAA) and secondly, to assess the performance of these features to differentiate between a right aortic arch with left duct (RAA-LD) in a blinded cohort of vascular rings.

METHODS

Review of records to identify surgically confirmed cases of DAA diagnosed prenatally from 2014 to 2018 (cohort-A). Prenatal echocardiograms were reviewed and the segments of the aortic arches anterior and posterior to the trachea, aortic isthmuses and the presence/absence of the Z-sign were described. The utility of these markers were assessed in a separate cohort (B) of fetuses with surgically confirmed cases of DAA or RAA-LD.

RESULTS

Cohort-A comprised 34 cases with DAA; there was a dominant RAA in 32/34 (94%) and balanced left aortic arch (LAA) and RAA in two cases. The proximal LAA was seen in 29/34 (85%), distal LAA in 15/34 (44%) and the LAA aortic isthmus in 4/34 (12%). The "Z" configuration was present in 29/34 (85%) cases. The most predictive marker for DAA in cohort-B was the Z-sign (sensitivity: 100%, specificity: 81%).

CONCLUSION

The "Z" sign is a useful differentiator between RAA-LD and DAA. The absence of visualization of the left aortic isthmus does not preclude the presence of a DAA.

Prenatal Diagnosis of Vascular Ring: Evaluation of Fetal Diagnosis and Postnatal Outcomes

BACKGROUND

The impact of fetal echocardiography on the diagnosis and outcomes of vascular ring has not been well examined. We hypothesized that prenatal detection of vascular ring has improved over time and that prenatal diagnosis of vascular ring is associated with earlier intervention and favorable outcomes.

METHODS

This is a single-center, retrospective study of the evolution and outcomes of prenatal diagnosis of vascular ring from 2000 to 2020. We compared clinical presentation, timing of surgical intervention, and outcomes between the prenatally and postnatally diagnosed cases during the same study period.

RESULTS

A total of 170 patients were included: 50 with prenatal and 120 with postnatal diagnosis of vascular ring. Prenatal diagnoses included 42 patients (84%) with right aortic arch (RAA), aberrant left subclavian artery (ALSCA), and a left-sided ductus arteriosus and eight (16%) patients with double aortic arch (DAA). The postnatal cohort consisted mainly of 90 patients (75%) with DAA and 22 (18%) with RAA-ALSCA. None of the postnatally diagnosed cases had undergone a fetal echocardiogram. Numbers (percentage) of prenatally diagnosed cases of vascular ring compared with the postnatal cases improved from 4/31 (13%), to 10/29 (34%), to 14/25 (56%), and to 22/35 (69%), respectively, during 2000-2005, 2005-10, 2010-15, and 2015-20 (P = .032). Vascular ring was an isolated abnormality in 84% and 85% of the prenatal and postnatal cohorts, respectively. Compared with the prenatal cohort, postnatally diagnosed patients with an isolated vascular ring were more frequently symptomatic (66% vs 48%, P < .03) and underwent cross-sectional imaging (69% vs 44%, P = .009) and surgery more frequently (79% vs 48%, P = .003). Surgery was performed at a later patient age (18 [2-147] months vs 4.8 [0.5-42] months, P = .01) and was more often associated with residual symptoms (27/81 [33%] vs 1/20 [5%], P = .01) in the postnatal cohort than in the prenatal cohort.

CONCLUSIONS

The diagnosis of vascular ring by fetal echocardiography has improved over time. A significantly higher incidence of RAA-ALSCA in the prenatal compared with the postnatal cohort suggests that patients with this form of vascular ring often do not present to medical attention with significant symptoms postnatally. Prenatal diagnosis of vascular ring was associated with a lower incidence of symptoms, less frequent use of cross-sectional imaging, earlier age at surgical intervention, and lower likelihood of residual symptoms.

Applications of Advanced Ultrasound Technology in Obstetrics

Over the years, there have been several improvements in ultrasound technologies including high-resolution ultrasonography, linear transducer, radiant flow, three-/four-dimensional (3D/4D) ultrasound, speckle tracking of the fetal heart, and artificial intelligence. The aims of this review are to evaluate the use of these advanced technologies in obstetrics in the midst of new guidelines on and new techniques of obstetric ultrasonography. In particular, whether these technologies can improve the diagnostic capability, functional analysis, workflow, and ergonomics of obstetric ultrasound examinations will be discussed.

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.