Fetal Aortic Arch Research Articles

EP01.38: The carotic‐subclavian artery index in the fetal aortic arch with classical branching and its variants in the second trimester

EP01.38: The carotic‐subclavian artery index in the fetal aortic arch with classical branching and its variants in the second trimester

Prenatally detected aortic arch anomalies and their consequences after birth

Aortic arch anomalies are frequently associated with cardiac or extracardiac malformations, chromosomal aberrations and postpartum esophagus/trachea compression. We aimed to establish the prevalence of associated cardiac and extracardiac malformations, the frequency of chromosomal aberrations in fetuses with the diagnosis of aortic arch anomalies and to assess the pregnancy and the postnatal outcome. Retrospective cohort study of all fetuses with aortic arch anomalies and genetic diagnosis in a tertiary referral obstetric and fetal cardiology centre between 2016 and 2020. Postpartum data were collected within 24 months after birth. In a cohort of 11.380 pregnant women, the prevalence of aortic arch anomalies was 0.25%. Among 28 cases of right aortic arch anomalies, in 27 fetuses prenatal genetic diagnosis was available. We diagnosed 4 fetuses with mirror-image branching (right sided V-sign) and 23 fetuses with U-sign (4 fetuses with complete double aortic arch). 18 cases (66%) were isolated. Associated anomalies were cardiac in 3 cases and extracardiac in 7 cases (33%). The most frequent cardiac anomaly was tetralogy of Fallot (2/27), the extracardiac anomalies were thymus hypoplasia, single umbilical artery and subclavian artery malformations. In 1 case (3.7%), fluorescent in situ hybridization diagnosed 22q11.2 microdeletion. 75% of fetuses with right sided V-sign were associated with conotruncal malformations. Pregnancy and postpartum outcome were known in 24 pregnancies. Postnatal diagnosis was different from prenatal in 2 cases, the concordance rate was 93%. Isolated cases resulted in live birth in 17/18 pregnancies (93%). The frequency of postpartum trachea/esophagus compression was 42,9% (9 cases) due to vascular ring, in 6 children (28,6%) operation was necessary. Fetal aortic arch anomalies are multidisciplinary diseases to be diagnosed by proper prenatal ultrasound examination. Associated fetal anomalies necessitate extended obstetric and cardiac sonography, invasive prenatal testing should be offered, and thorough postnatal long-term follow-up is recommended. Orv Hetil. 2023; 164(28): 1111-1120.

OC01.08: The applied research of the diagnosis of fetal aortic arch branch abnormalities by the combination of prenatal ultrasound and cMRI

OC01.08: The applied research of the diagnosis of fetal aortic arch branch abnormalities by the combination of prenatal ultrasound and cMRI

Prenatal Diagnosis of Bovine Aortic Arch Anatomic Variant.

Fetal aortic arch development is an early and complex process that depends on many genetic and environmental factors. The final aortic arch varies greatly; it may take the form of a normal arch, anatomic variant (AAAV) with a common origin to that of the innominate artery and left common carotid artery (formerly known as “bovine aortic arch” (with an incidence of up to 27%)) or one of multiple pathological conditions. The present study aimed to establish the feasibility and impact of prenatal anatomic arch variants’ diagnosis. A retrospective study of 271 fetal second- and third-trimester anomaly scans was performed in our tertiary center. Examinations that evaluated the sagittal aortic arch were included and the branching pattern was assessed. Additionally, a literature data search based on the terms “common origin of innominate artery and left common carotid artery”, “bovine arch”, “bovine aortic” and “aortic arch anomalies” was performed. Results that referred to prenatal AAAV were retained and the papers evaluated. In our study, the AAA incidence was 1.93%, with 4 out of 5 cases being arch type B. All cases had minor associated conditions but a good postnatal outcome. An anatomic aortic variant with a common IA and LCCa prenatal diagnosis was found in a small number of studies; most of the cases described in pediatric and adult series were related to cardiac surgery for stenting, aneurysm or thoracic-associated diseases. The incidence of AAAV varied from 6 to 27% depending on the population studied (highest incidence in African individuals). The variant was highly associated with aortic dissection, pulmonary and cerebral embolism and increased risks of incidents during surgery. Diagnosing AAAV during a routine anatomic scan is feasible and diagnoses can be made when anomaly scans are performed. Awareness of the condition is important for postnatal surgery when other cardiac anomalies are found; this can prevent accidents with simple changes to the patient’s lifestyle, and, in the case of surgery, means we can adopt the correct surgical approach.

Abstract 13314: Development of a Computational Fluid Dynamics Model for Assessing Hemodynamics in Aortic Arches in Human Fetuses

Background and Objective: The hemodynamics of fetal circulation and its alterations, as in cases of congenital heart defects (CHD), have been investigated in instrumented animal models or in human fetuses by noninvasive fetal echocardiography and Doppler (FED). There is little data in computational modeling of fetal circulation due to challenges in fetal cardiac imaging and the availability of validation methodologies. This study aims to develop and validate a computational model for assessing hemodynamics in aortic and ductal arches in human fetuses. Methods: Figure 1 shows our computational workflow. The process started by preparing a reconstructed 3D aortic and ductal arch anatomy derived from 3D FED. Then, the computational model was built and validated using clinical data from five human fetuses. The primary output was the velocity waveform at the aortic isthmus (AoI), validated using tracings from spectral Doppler. Results: Upon superimposing the reconstructed fetal aortic arch anatomies onto the original 3D FED stack, our results demonstrated a precise rendering of each subject’s unique vessel structure. Simulations were run for ten cardiac cycles, with each velocity waveform at the AoI showing a discrepancy of less than 15% when compared with the Doppler echocardiography tracings. These findings indicate a good agreement between our computational model and the FED data. Conclusion: This study presents the development and validation of a computational model for assessing patient-specific hemodynamics in the aortic arches of human fetuses. Continued investigation is warranted to further validate and apply this approach to improve the diagnosis, prognosis, and treatment of CHD in human fetuses.

Diagnostic quality of 3Tesla postmortem magnetic resonance imaging in fetuses with and without congenital heart disease

Postmortem confirmation of prenatally diagnosed congenital heart disease after termination of pregnancy and evaluation of potential cardiac defects after spontaneous fetal or neonatal death are essential. Conventional autopsy rates are decreasing, and 1.5Tesla magnetic resonance imaging has demonstrated limited diagnostic accuracy for postmortem cardiovascular assessment. This study aimed to evaluate the feasibility and image quality of cardiac 3Tesla postmortem magnetic resonance imaging and to assess its diagnostic accuracy in detecting fetal heart defects compared with conventional autopsy. Secondarily, the study aimed to explore whether clinical factors affect the quality of 3Tesla postmortem magnetic resonance imaging. A total of 222 consecutive fetuses between 12 and 41 weeks' gestation, who underwent 3Tesla postmortem magnetic resonance imaging and conventional autopsy after spontaneous death or termination of pregnancy for fetal malformations, were included. First, 3Tesla postmortem magnetic resonance imaging of each fetus was rated as diagnostic or nondiagnostic for fetal cardiac assessment by 2 independent raters. The image quality of individual cardiac structures was then further evaluated by visual grading analysis. Finally, the presence or absence of a congenital heart defect was assessed by 2 radiologists and compared with autopsy results. Overall, 87.8% of 3Tesla postmortem magnetic resonance imaging examinations were rated as diagnostic for the fetal heart. Diagnostic imaging rates of individual cardiac structures at 3Tesla postmortem magnetic resonance imaging ranged from 85.1% (atrioventricular valves) to 94.6% (pericardium), with an interrater agreement of 0.82 (0.78-0.86). Diagnostic imaging of the fetal aortic arch and the systemic veins at 3Tesla postmortem magnetic resonance imaging was possible from 12+5 weeks' gestation onward in 90.1% and 92.3% of cases, respectively. A total of 55 fetuses (24.8%) had at least 1 cardiac anomaly according to autopsy, 164 (73.9%) had a normal heart, and in 3 fetuses (1.4%), autopsy was nondiagnostic for the heart. Considering all examinations rated as diagnostic, 3Tesla postmortem magnetic resonance imaging provided high diagnostic accuracy for the detection of fetal congenital heart defects with a sensitivity of 87.8%, a specificity of 97.9%, and concordance with autopsy of 95.3%. 3Tesla postmortem magnetic resonance imaging was less accurate in young fetuses (<20 weeks compared with ≥20 weeks; P<.001), in fetuses with low birthweight (≤100 g compared with >100 g; P<.001), in cases after spontaneous fetal death (compared with other modes of death; P=.012), in cases with increasing latency between death and 3Tesla postmortem magnetic resonance imaging (P<.001), and in cases in which there was a high degree of maceration (maceration score of 3 compared with a score from 0 to 2; P=.004). Diagnostic 3Tesla postmortem magnetic resonance imaging assessment of the fetal heart is feasible in most fetuses from 12 weeks' gestation onward. In diagnostic images, sensitivity and, particularly, specificity in the detection of congenital heart disease are high compared with conventional autopsy. Owing to its high diagnostic accuracy, we suggest that 3Tesla postmortem magnetic resonance imaging may serve as a suitable imaging modality with which to direct a targeted conventional autopsy when pathology resources are limited or to provide a virtual autopsy when full autopsy is declined by the parents.

Abstract 14543: Diminished Aortic Flow in Fetus and Its Implications in Development of Aortic Coarctation and Arch Interruption: A 3d/4d Fetal Echocardiography and Computational Fluid Dynamics Study

Background and Objectives: During critical windows of cardiac morphogenesis and remodeling, altered intrauterine hemodynamics may lead to congenital heart defects, such as aortic arch abnormalities. We sought to investigate the effects of diminished flow in the fetal aorta to understand the cause, improved diagnosis, and prognosis of coarctation of aorta (CoA) and interrupted aortic arch (IAA). Methods: Computational fluid dynamics (CFD) model of aortic and ductal arches was built based on dynamic 3D/4D spatiotemporal image correlation (STIC) fetal echocardiography (FE) and Doppler images from a normal fetus. Pulsatile hemodynamics, including velocity, pressure gradient, and wall shear stress (WSS), were stimulated as aortic flow decreased from 100% to 80%, 60%, 40%, and 20% by CFD, with accompanying ductal flow increased proportionally to maintain combined cardiac output (Figure). Results: As aortic flow diminished from 100% to 20% progressively, velocity, pressure, and WSS decreased in systole and diastole in aortic arch and isthmus. As aortic flow decreased, the flow structures changed, resulting in a reduction of WSS in the aortic isthmus, especially on the posterior wall. There was a “zero flow zone” between the left carotid and subclavian arteries when aortic flow decreased to 40% of baseline, and another one between innominate and left carotid arteries when it decreased to 20%. Pearson correlation analysis showed significant correlations between aortic flow, pressure, velocity, and WSS (r=0.883 - 1.000, P=0.047 - 0.001) at aortic isthmus. Conclusions: It is feasible to create a hemodynamic model of human fetal aortic arch using 3D/4D FE and CFD. The alterations of flow variables, especially WSS, and the “zero flow zones" in the aorta from progressive aortic flow reduction suggest the "flow-dependency” of the fetal aortic arch development and a unifying hypothesis of diminished flow in the pathogenesis of CoA and IAA.

Fetal double aortic arch: prenatal sonographic and postnatal computed tomography angiography features, associated abnormalities and clinical outcomes

BackgroundFetal double aortic arch (DAA) malformation is a rare congenital heart disease with few reported cases in the literature. We aimed to investigate the characteristics of prenatal ultrasound and postnatal computed tomography angiography (CTA) of DAA and to describe the associated anomalies and clinical outcomes to improve prenatal diagnosis and assist in perinatal management.MethodsThe obstetric ultrasound imaging databases of seven tertiary referral centers were reviewed retrospectively to identify fetuses with a prenatal diagnosis of DAA between January 2013 and December 2018. Ultrasonographic findings, associated anomalies, genetic abnormalities, postnatal CTA images, and long-term postnatal outcomes were evaluated.ResultsA total of 36 cases out of 40 prenatally diagnosed DAA fetuses were confirmed by postnatal diagnosis (fetal autopsy, CTA, and surgery). In this cohort of 36 confirmed cases, 24 (67%) were isolated anomalies, while 12 (33%) were associated with intracardiac or extracardiac anomalies, and 2 (6%) had a 22q11.2 chromosome deletion. Among nine cases of pregnancy termination with a fetal autopsy, 7 had other abnormalities. Among the remaining 27 live births, 16 (59%) were asymptomatic and 11 (41%) received surgical treatment due to tracheal or esophageal compression symptoms, all with satisfactory outcomes. Prenatal echocardiography showed that DAA was mainly characterized by a bifurcation of the ascending aorta into the right and left aortic arch and the formation of a complete O-shaped vascular ring around the trachea on the three-vessel tracheal view. A variant in the aortic arch branching pattern was found for the first time. The airway obstruction, branching pattern, and atretic arch of DAA were clearly shown by postnatal CTA.ConclusionsFetal DAA has unique features on prenatal echocardiography and postnatal CTA, and systematic prenatal examination and timely postnatal CTA evaluation are required. A certain proportion of intracardiac and extracardiac abnormalities are associated with DAA, but the probability of chromosome abnormalities is low, especially for isolated DAA.The clinical outcomes of isolated DAA are favorable, even if surgery is performed due to symptoms. Determining whether other malformations or chromosomal anomalies exist is crucial for prognosis evaluation and prenatal counseling.

VP14.10: Prenatal diagnosis of vascular rings and its clinical significance in postnatal life

Prenatal detection of vascular rings has increased over the past two decades. These lesions may be asymptomatic or cause respiratory and/or gastrointestinal (GI) symptoms from tracheal or esophageal compression. Symptomatology dictates surgical correction. We present 12 cases of prenatally diagnosed vascular rings with their postnatal course. We reviewed all fetal aortic arch anomalies diagnosed from 2016–2019 at our institution. We collected prenatal and postnatal diagnosis, cardiac and non-cardiac anomalies, genetics, postnatal clinical course, symptoms and surgical outcomes. 32 fetal echocardiograms revealed arch sidedness and branching anomalies; 25 isolated right aortic arch (RAA) with mirror image branching, 6 isolated aberrant right subclavian artery, 1 isolated aberrant left subclavian, 11 RAA with aberrant left subclavian and 1 double aortic arch. Out of the 12 vascular ring patients, no genetic syndromes were identified prenatally or postnatally despite the risk for 22q11 deletion with RAA. Postnatal imaging confirmed the prenatal diagnosis in all 12 patients. Associated congenital heart disease included ventricular septal defect in one patient. Associated extracardiac disease included pelvic kidney and tracheobronchomalacia. 7 (58%) remained asymptomatic and 5 (42%) reported respiratory and/or GI symptoms. Average age of symptom onset was 67 days. 3 (25%) patients required surgery for respiratory and GI symptoms at mean age of 7.3 months. Mean age of clinical follow-up was 6.4 months. We found that the majority of prenatally diagnosed vascular rings remain asymptomatic and do not have concomitant intracardiac or extracardiac disease or genetic syndromes. Presently, there are no prenatal markers to predict postnatal surgery. Further research may identify prenatal markers of respiratory or gastrointestinal compromise.

The Features of Pregnancy, Early Neonatal Period and Tactics of Surgical Treatment in Newborn with Hypoplastic Aortic Arch (First-Hand Experience)

Aortic pathology occurs in 10% of all newborn with congenital heart diseases (CHD). According to the data of various authors, in 50–80% of cases coarctation of aorta is accompanied by hypoplastic aortic arch. The newborn with such diagnosis represent a unique cohort of children who remain in severe condition and require immediate surgical intervention. Despite the significant development of diagnostic opportunities of radiographic methods, aortic arch patho­ logy remains one of the most difficult diagnoses in prenatal diagnostics.&#x0D; The objective of the study is to provide rationale for perinatal prognosis based on the analysis of pregnancy course, condition of the fetus and newborn in order to provide timely diagnosis and perform cardiosurgical interventions in patients with aortic arch pathology.&#x0D; Materials and methods. In the period from 2011 to 2019 at the State Institution “Institute of Pediatrics, Obstetrics and Gynecology of NAMS of Ukraine” and State Institution “National Amosov Institute of Cardiovascular Surgery of the NAMS of Ukraine” 121 pregnant women with fetal aortic arch hypoplasia were observed, followed and gave birth according to the algorithm developed by our team. The most optimal terms for fetus examination were weeks 20–22 and 30–32 of pregnancy. Patients with hypoplastic aortic arch as part of hypoplastic left heart syndrome were excluded from the analysis of tactics and results of surgical treatment since this category of patients requires separated study. Among 53 patients with hypoplastic aortic arch (36 patients with isolated hypoplastic aortic arch, and 17 patients with that combined with other CHD), 43 patients required surgical treatment after additional in-patient examination.&#x0D; Results and discussion. Analysis of the pregnancy course in women with fetal aortic arch hypoplasia showed that the number of multifetal pregnancies (including those having occurred after the use of extracorporeal technologies) was higher in pregnant women of the main group. Also, the percentage of threat of termination of pregnancy in the early term was high threatened miscarriage in the early stages of pregnancy was higher, and, vice versa, the threat of premature birth was lower. It is worth noting that 7 (5.7%) children had the appearance of “completely healthy child” in the first day of life, which confirms the importance of prenatal echocardiography in the timely diagnosis of critical CHD. To analyze the effectiveness of prenatal diagnosis and timely referral of patients to a specialized cardiac surgery center, it was found that the number of complications at the preoperative stage was statistically significantly higher in the group of patients without prenatal diagnosis.&#x0D; Conclusion. In case of diagnosed or suspected fetal aortic hypoplasia (isolated or combined with other abnormalities) a multidisciplinary case management team should be involved to determine further perinatal tactics and timing of cardiac surgery which will significantly reduce pre- and postoperative complications.

Bovine aortic arch: Prevalence in human fetuses.

"Bovine aortic arch" is the second most common variant of aortic arch branching, in which only two branches originate directly from the aorta. The prevalence of this condition has been reported in different studies to be around 6% in human fetuses and 11-27% in the adult population. In this study, we describe the prevalence of bovine aortic arch in fetuses, and assess the prevalence of concomitant fetal anomalies. A retrospective analysis of 417 fetuses between 15-40 weeks of gestation. Data regarding branching of the fetal aortic arch and other fetal anomalies were collected by fetal echocardiography and/or fetal ultrasonography. A bovine arch was found in 20/413 fetuses (4.8%, 95CI 3.1-7.3%), of whom 14/310 (4.5%) had no fetal anomalies, and 6/77 (7.8%) exhibited minor changes (P = .241). None of the 26 fetuses with major anomalies had a bovine arch. Fetuses in this study had a lower prevalence of bovine aortic arch than that previously reported in adults, most probably due to differences in the population examined. This study was underpowered to determine that bovine arch is a common anatomic variant, and is not associated with fetal anomalies.

P08.10: Analysis of STIC flow imaging characteristics of fetal double aortic arch and right‐side aortic arch with mirror carotid branch

P08.10: Analysis of STIC flow imaging characteristics of fetal double aortic arch and right‐side aortic arch with mirror carotid branch

EP12.11: Investigation of seven cases of fetal double aortic arch

EP12.11: Investigation of seven cases of fetal double aortic arch

OC21.03: Dynamic fetal cardiac magnetic resonance imaging using Doppler ultrasound gating in the assessment of the fetal aortic arch: a feasibility study in comparison to fetal echocardiography

OC21.03: Dynamic fetal cardiac magnetic resonance imaging using Doppler ultrasound gating in the assessment of the fetal aortic arch: a feasibility study in comparison to fetal echocardiography

Prenatal echocardiography in the diagnosis of fetal double aortic arch

Objective To explore the way of prenatal echocardiography in the diagnosis of fetal double aortic arch. Methods The data of fetuses diagnosed as double aortic arch in 6 prenatal centers in Hunan in echocardiograms performed at 20-36 weeks of gestation from 2013 to 2018 were reviewed. The characteristics of echocardiographic with double aortic arch, and the associated malformations were observed, the clinical outcome were analyzed. Results The main echocardiographic features of the double aortic arch were three-vessel-tracheal views, which showed a bifurcation of the ascending aorta and a ring consisted of aortic right and left arch. From this retrospective analysis, 29 double aortic arches were identified, which 8 cases (28%) combined with cardiac defect and extracardiac abnormalities, 1 case with 22q11 deletion. Among them, 5 cases were confirmed by autopsy, 24 cases were diagnosed by computed tomography angiography(8 cases were confirmed by operation). Conclusions Systematic prenatal echocardiography in the diagnosis of fetal double aortic arch has significant clinical value in the cliagnose of double aortic arch, whether it is associated with other malformations and is important for assessing fetal prognosis. Key words: Ultrasonography, prenatal; Fetal; Double aortic arch

Fetal Right Aortic Arch: A Quantitative Method of Outcome Prediction

Objective: To investigate right aortic arches (RAA) quantitatively and risk-stratify fetuses with RAA prenatally.Method: A total of 143 singleton fetuses were enrolled. Four measurements were studied, including the angle and distance between the aortic arch (AO) and ductal arch (DA), the diameters of the AO and DA, and the distance growth rate (DGR).Result: A significant increase in mean distance was observed in the study group (4.89 ± 1.07 mm) compared to the control group (1.62 ± 0.33 mm, p<.01). The distance increased from the second (1.52 ± 0.35 mm, p<.01, 4.06 ± 0.78 mm, p<.01) to third trimester (1.71 ± 0.29 mm, p<.01, 5.13 ± 1.10 mm, p<.01) in the normal and study groups. Fetuses with abnormalities in addition to RAAs had significantly lower growth rates (12.4 ± 5.2%) than those with an isolated RAA (33.7 ± 12.0%).Conclusion: Parameters, especially DGR, may be clinically significant. DGR may be restricted when an RAA exists with other malformations. Decreasing DGR in fetuses with RAAs suggests the presence of other malformations.

Clues and techniques of prenatal ultrasonographic diagnosis for fetal aortic arch anomalies

Objective To explore the ultrasonographic features, diagnostic clues and methods of fetal aortic arch anomalies, and to improve the diagnosis rate of prenatal ultrasonography for fetal aortic arch anomalies. Methods Fetuses with aortic arch anomalies diagnosed by prenatal ultrasound were selected as the study objects. The prenatal ultrasonographic features of the three views of the aortic arch were carefully observed. The three views included the followings: the transverse view(the view of three vessels and trachea), the sagittal view (the longitudinal view of the aortic arch), and the coronal view (the coronal view of the descending aorta). The prenatal diagnostic clues and diagnostic techniques of aortic arch anomalies were summarized and analyzed. Results Eighty-one cases with aortic arch anomalies were followed up. Fifteen cases were left-sided aortic arch and left-sided ductus arteriosus with aberrant right subclavian artery, 22 cases with right aortic arch and left-sided ductus arteriosus with aberrant left subclavian artery, 4 cases were mirror right aortic arch and left-sided ductus arteriosus, 2 cases were mirror right aortic arch and right-sided ductus arteriosus, 11 cases were double aortic arch, 23 cases were coarctation of the aorta, and 4 cases were interruption of aortic arch. Among them, 27 cases were complicated with other cardiac and extra-cardiac malformations and 13 cases with chromosomal abnormalities. Prenatal ultrasonographic clues for diagnosis of coarctation of the aorta included the three vessels and trachea view showing small diameter and disproportion to the diameter of the ductus arteriosus. And the longitudinal view of the aortic arch was helpful for showing the position and the extent of coarctation of the aorta. Prenatal ultrasonographic clues for diagnosis of interruption of aortic arch were that the three vessels and trachea view and the longitudinal view of the aortic arch showed the interruption between aortic arch and descending aorta. And the abnormal combination cases of the aortic arch segments also had their corresponding diagnostic clues. These clues included that the three vessels and trachea view showed abnormal position, arrangement and running of the branches of the aortic arch. And the coronal view of the descending aorta also showed abnormal changes in the branches of aortic arch. Conclusions Various types of congenital aortic arch anomalies have characteristic ultrasonography and their corresponding diagnostic clues and methods. The combined use of the three views of the aortic arch is effective in prenatal diagnosis for aortic arch anomalies. Key words: Ultrasonography, prenatal; Aortic arch anomalies; Diagnostic clues

P13.07: Fetal aortic arch and its branches anomalies: prenatal ultrasound, vascular cast and gene detection

P13.07: Fetal aortic arch and its branches anomalies: prenatal ultrasound, vascular cast and gene detection

Strategies for Accurate Diagnosis of Fetal Aortic Arch Anomalies: Benefits of Three-Dimensional Sonography With Spatiotemporal Image Correlation and a Novel Algorithm for Volume Analysis

Obtaining an accurate diagnosis of fetal aortic arch anomalies is often difficult with traditional two-dimensional (2D) sonography. Thus, the aim of this study was to assess the value of three-dimensional (3D) sonography with spatiotemporal image correlation for diagnosing fetal aortic arch anomalies using a novel algorithm for 3D volume analysis. Two-dimensional and 3D echocardiographic image data from 300 normal fetuses and 30 fetuses with aortic arch anomalies were retrospectively reviewed. Grayscale and high-definition flow imaging data were available for 2D echocardiography. Three-dimensional volumes were acquired in parasagittal views with high-definition flow imaging information. Volume postprocessing was performed using a novel algorithm to obtain 3D tomographic ultrasound imaging slices and color-rendered images. Detection of aortic arch positions, aberrant brachiocephalic patterns, and aortic arch anomalies was compared for 2D and 3D modalities. Postnatal echocardiography was used as the truth standard in assessing aortic anatomy. In total, four cases of double aortic arch, 21 cases of right aortic arch, one case of retroesophageal aortic arch, and four cases of left aortic arch with aberrant right subclavian arteries were included. Inter- and intraobserver agreement were excellent for 2D and 3D modalities. The 3D modality offered better sensitivity and accuracy compared with 2D imaging for the detection of brachiocephalic anomalies (P<.01) and arch anomalies (P<.01) but comparable sensitivity for arch position. There was no difference in specificity for both modalities. The proposed novel algorithm for volume postprocessing ensures that 3D reconstructed images are obtained with high repeatability. The addition of 3D spatiotemporal image correlation to fetal echocardiography may offer a more accurate diagnosis for arch anomalies.

Fetal aortic arch and its branches anomalies: prenatal ultrasound, vascular cast and gene detection

Objective To explore the application values of prenatal ultrasound, vascular cast in the diagnosis of fetal aortic arch and its branches anomalies and to analyze the genetic characteristics by gene detection. Methods Twenty-two cases of the vascular cast specimens of the fetal aortic arch and its branches anomalies were analyzed and studied by comparing with their prenatal ultrasonography. Then the characteristics of each type of fetal aortic arch and its branches anomalies, the missed diagnosis and misdiagnosis were summarized and the results of their gene detection were also analyzed. Results The 22 cases of fetal aortic arch and its branches anomalies were as follows: 2 cases of double aortic arch showed the ascending aorta was divided into two branches after converging as the descending aorta. Three cases were left aortic arch with aberrant right subclavian artery. Twelve cases were right aortic arch: 8 cases were right aortic arch with mirror-image branching, 3 cases were right aortic arch with aberrant left subclavian artery, 1 case was right aortic arch with isolated left subclavian artery. Of the 8 right aortic arch with mirror-image branching, 3 cases of left arterial duct showed the vertical walking between the fusion site of the left innominate artery and the pulmonary artery. Right aortic arch with aberrant left subclavian artery with arterial duct showed U shaped vascular ring. Five cases were other types, including 2 cases of the coarctation of aortic arch, 1 case of interrupted aortic arch, 1 case of pulmonary artery sling, and 1 case of abnormal origin of right pulmonary artery. The ultrasonic missed diagnosis were the 6 deformities: 3 cases of arterial duct and 3 cases of aberrant subclavian artery. The ultrasonic misdiagnosis were the 5 deformities: 2 cases of arterial duct location, 1 case of aberrant subclavian artery, 1 case of isolated left subclavian artery, and 1 case of the coarctation of aortic arch. Genetic test results: In the 18 cases of the genetic detection, 2 cases were positive, 1 case was 22q11.2 microdeletion syndrome and 1 case was carrying KMT2D gene variant. Conclusions There are various kinds of fetal aortic arch and its branches anomalies, which are often associated with intracardiac malformations and venous branches variation. And prenatal ultrasound is of great value in diagnosing them.Vascular cast can visually display their characteristic changes, which is helpful to improve the differential diagnosis of the different aortic arch and its branches anomalies. The detailed genetic detection can improve the further understanding of its etiology. Key words: Ultrasonography, prenatal; Fetus; Aortic arch anomalies; Vascular cast; Gene detection