Aberrant Right Subclavian Artery: Correlation Between Fetal and Neonatal Abnormalities and Abnormal Genetic Screening or Testing

Associated Anomalies and Outcome in Patients with Prenatal Diagnosis of Aortic Arch Anomalies as Aberrant Right Subclavian Artery, Right Aortic Arch and Double Aortic Arch

We aimed to evaluate retrospectively associated anomalies and outcome in prenatal aortic arch anomalies (AAAs). We included ninety patients with aberrant right subclavian artery (ARSA), right aortic arch (RAA) with mirror image branching (RAA-mirror) or aberrant left subclavian artery (RAA-ALSA) and double aortic arch (DAA) between 2011 and 2020. In total, 19/90 (21.1%) had chromosomal anomalies, the highest rate being within the ARSA subgroup (17/46, 37%). All (13/13) of the RAA-mirror subgroup, 10/27 (37.0%) of RAA-ALSA, 13/46 (28.3%) of ARSA and 0/4 within the DAA subgroup had additional intracardiac anomaly. The rate of extracardiac anomalies was 30.7% in RAA-mirror, 28.3% in ARSA, 25.0% in DAA and 22.2% in the RAA-ALSA subgroup. A total of 42/90 (46.7%) had isolated AAAs: three (7.1%) with chromosomal anomalies, all trisomy 21 (3/26, 11.5%) within the ARSA subgroup. Out of 90, 19 (21.1%) were lost to follow-up (FU). Two (2.2%) intrauterine deaths occurred, and six (6.7%) with chromosomal anomalies terminated their pregnancy. In total, 63 (70.0%) were liveborn, 3/63 (4.8%) with severe comorbidity had compassionate care and 3/60 (5.0%) were lost to FU. The survival rate in the intention-to-treat cohort was 53/57 (93%). Forty-one (77.4%) presented with vascular ring/sling, two (4.9%) with RAA-ALSA developed symptoms and one (2.4%) needed an operation. We conclude that intervention due to vascular ring is rarely necessary. NIPT could be useful in isolated ARSA cases without higher a priori risk for trisomy 21 and after exclusion of other anomalies.

Associated congenital anomalies and genetic anomalies in fetuses with isolated and non-isolated aberrant right subclavian artery

OBJECTIVE

This study's aim was to determine the prevalence of chromosomal anomalies in fetuses with isolated and non-isolated aberrant right subclavian artery (ARSA) and to evaluate its association with other congenital anomalies.

METHODS

From September 2018 to October 2021, 668 ARSA cases were diagnosed by prenatal ultrasound in our hospital; cases with missed visits and a lack of chromosomal findings were excluded and 363 cases were eligible for enrollment. General information, ultrasound presentation, chromosomal findings and pregnancy outcomes were retrospectively analyzed.

RESULTS

Among the 363 cases, 296 were isolated, and 67 were associated with structural abnormalities or soft marker abnormalities. The proportion of fetuses with chromosomal abnormalities in the isolated ARSA group was significantly lower than that in the non-isolated ARSA group (p < .001). In the non-isolated ARSA group, 22 cases were combined with other soft marker abnormalities and 45 cases were combined with structural abnormalities. The most frequent structural abnormality coexisting with ARSA was cardiac malformations (38.81%).

CONCLUSION

The most common combined malformation in ARSA is intracardiac malformation. Isolated ARSA has a low risk of chromosomal abnormalities, so invasive chromosomal testing is not recommended. Non-isolated ARSA has a high incidence of chromosomal abnormalities, so early karyotyping should be recommended.

Isolated aberrant right subclavian artery: an underlying clue for genetic anomalies

OBJECTIVE

Aberrant right subclavian artery (ARSA) is known to be associated with specific chromosomal abnormalities. However, there is no agreement regarding clinical decisions related to isolated ARSA. This study evaluated the association between ARSA and genetic abnormalities to provide evidence for prenatal consultation and the postpartum management of isolated ARSA.

METHODS

This single-center cross-sectional study involved fetuses diagnosed with ARSA between January 2014 and May 2021. A range of data was recorded for each patient, including screening ultrasound, fetal echocardiograms, genetic results, postnatal information, and follow-up records.

RESULTS

ARSA was detected in 151 fetuses, of which 136 were considered isolated cases. The remaining 9.9% (15/151) of cases had cardiac and/or extracardiac abnormalities or soft markers. Data from karyotype analysis and chromosomal microarray analysis (CMA) were available for 56 and 33 (out of 56) fetuses, respectively. Genetic abnormalities were detected in 10.7% of fetuses (6/56). Of these, 4.4% (2/45) and 36.4% (4/11) were associated with isolated and non-isolated ARSA, respectively, with a significant difference between these two groups regarding the frequency of genetic abnormality (p = 0.011). The analysis detected Klinefelter Syndrome (47, XXY) and 16p11.2 microdeletion in two isolated cases. One case each of trisomy 21 and 22q11.2 deletion, and another case of 47, XXY, were detected in fetuses with cardiac anomalies. Partial 5q deletion was found in a fetus with extracardiac malformations. In total, 141 of the fetuses survived after birth; termination of pregnancy was performed for 10 fetuses; only two fetuses had mild symptoms of dysphagia.

CONCLUSION

ARSA may be an underlying ultrasonic clue for genetic anomalies even in isolated ARSA. Fetuses with isolated ARSA cannot be ruled out for invasive antenatal diagnosis.

Aberrant right subclavian artery: case report and literature review

The aberrant right subclavian artery, also known as the arteria lusoria, is the most common aortic arch anomaly, occurring in 0.5 to 1% of the population. There is a higher prevalence in women and it is usually associated with other anatomical variations, such as the non-recurrent laryngeal nerve, present in 86.7% of cases. In the majority of cases, the aberrant right subclavian artery causes no symptoms. We describe this anomaly in an 82-year-old, hypertensive, and asymptomatic patient who had undergone a thoracoabdominal angiography to investigate a chronic DeBakey type III aortic dissection with dilation of the descending aorta. The aberrant right subclavian artery followed a retroesophageal course and was associated with a Kommerell diverticulum. In view of its rarity, we conducted an integrative bibliographic review of literature from the last 6 years indexed on the Medline, UpToDate, Lilacs, Scielo, and Portal Capes databases and discuss the most frequent anatomical changes, symptomatology, and therapeutic management adopted.

Artéria subclávia direita aberrante: relato de caso e revisão de literatura

Resumo A artéria subclávia direita aberrante, também conhecida como artéria lusória, é a anomalia do arco aórtico mais comum, ocorrendo entre 0,5 e 1% da população. Possui prevalência em mulheres e normalmente está associada a outras variações anatômicas, como o nervo laríngeo não recorrente, presente em 86,7% dos casos. Em sua maioria, a artéria subclávia direita aberrante não apresenta sintomas. Descrevemos essa alteração em uma paciente de 82 anos, hipertensa e assintomática, que havia sido submetida a uma angiotomografia toracoabdominal para a avaliação de uma dissecção crônica tipo III (DeBakey) associada à dilatação de aorta descendente. No achado, a artéria subclávia direita aberrante apresentava percurso retroesofágico associado a um divertículo de Kommerell. Devido à raridade, realizamos revisão bibliográfica integrativa das bases de dados MEDLINE, UpToDate, LILACS, SciELO e Portal CAPES dos últimos 6 anos e discutimos as alterações anatômicas mais frequentes, a sintomatologia e as condutas terapêuticas adotadas.

Prenatal diagnosis of aberrant right subclavian artery: a literature review

The primary aim of this review is to estimate the prevalence of ARSA both in euploid fetuses as well as in fetuses with Down Syndrome. Secondary objectives were to estimate the association of ARSA with cardiac anomalies and chromosomal defects, especially trisomy 21 and 22q11 deletion (DiGeorge Syndrome). The incidence of ARSA in normal population varies from 0.35% to 3.5%, based on different studies. Since the first reported association between ARSA and trisomy 21 in 2015 until today, several studies have emerged to confirm different degrees of this correlation. Indeed, ARSA appears to be a clinically useful prenatal ultrasound marker for trisomy 21. Particularly, most recent studies concluded that ARSA as a non-isolated finding can be used as screening for Down syndrome. However, when ARSA is an isolated finding, various studies proved that there is no significant correlation with Down syndrome. Apart from these, ARSA appears to be associated with other chromosomal abnormalities, such as 22q11 deletion, cardiac defects and other morphological anomalies. As a conclusion ARSA should be characterized as isolated or non-isolated, as the non - isolated ARSA appears to be a clinically useful marker of Down syndrome and thus, additional testing is required when diagnosed.

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.

Fetal Aberrant Right Subclavian Artery: Associated Anomalies, Genetic Etiology, and Postnatal Outcomes in a Retrospective Cohort Study

BACKGROUND

Aberrant right subclavian artery (ARSA) is becoming increasingly common in fetuses. However, there are relatively fewer studies regarding the genetic etiology of ARSA. We performed a genetic analysis of fetuses with ARSA and followed up on the pregnancy outcomes to evaluate the prognosis of the fetuses, providing information for prenatal and eugenic consultations.

METHODS

This retrospective study included 112 pregnant females whose fetuses were diagnosed with ARSA from December 2016 to February 2021. Fetal karyotype analysis and single-nucleotide polymorphism (SNP) array were performed.

RESULTS

The 112 fetuses were divided into two groups: the isolated ARSA group (n = 48, 42.9%) and the non-isolated ARSA group (ARSA with other ultrasound abnormalities, n = 64, 57.1%). The total rate of pathogenic copy number variation (CNV) observed using karyotype analysis (3/8) and SNP array (5/8) was 7.1% (8/112). The rates of pathogenic CNV in the isolated and non-isolated ARSA groups were 4.2% (2/48) and 9.4% (6/64), respectively. No significant difference was observed between the two groups (P = 0.463). The results of genetic analysis influenced the parents' decision to terminate the pregnancy. During the follow-up examination, fetuses with ARSA without pathogenic CNV were found to have normal growth and development after birth.

CONCLUSION

Fetuses with isolated ARSA have a low probability of being diagnosed with pathogenic CNV. However, when ARSA is complicated with other ultrasound abnormalities, the risk of pathogenic CNV remarkably increases. Prenatal genetic counseling and SNP-array should be recommended for better assessment of fetal prognosis.

Chromosomal Microarray Analysis for the Fetuses with Aortic Arch Abnormalities and Normal Karyotype

Background

Aortic arch abnormalities (AAA) are abnormal embryologic developments of the aorta and its branches. Their outcomes often depend on their association with other congenital diseases and genetic testing results.

Objective

This study aimed to evaluate the yield of chromosomal microarray analysis (CMA) in fetuses with different patterns of AAA and normal karyotype.

Methods

Data from 158 pregnancies referred for prenatal CMA testing due to fetal AAA were obtained between April 2016 and April 2019. Fetuses with isolated AAA, AAA accompanied by soft ultrasound markers, and AAA with other ultrasound malformations were classified into groups A, B, and C, respectively. Cases with detectable karyotype aberrations were excluded from the study.

Results

Twenty cases (12.7%) of submicroscopic anomalies were detected in 158 cases with normal karyotype, comprising 16 cases (10.1%) of clinically significant variants, two cases (1.3%) of variants of unknown significance, and two variants (1.3%) that were likely benign. Microdeletion of 22q11.2 accounted for 25% (4/16) of the clinically significant variants. The overall incremental yields by CMA in group A, group B, and group C were 1.8%, 2.3%, and 24.1%, respectively. Except for double aortic arch, the incremental yield of clinical significant findings for each type of AAA in group C was much higher than that in group A and group B. In group A, a clinically significant variant was only detected in one fetus with right aortic arch (RAA) (1.8%, 1/57).

Conclusions

In addition to 22q11.2 microdeletion, many other clinically significant submicroscopic variants are present in fetuses with AAA, especially in fetuses with other ultrasound malformations. Although CMA is always recommended in the presence of any malformation in many countries, our results suggest insufficient evidence to recommend CMA in fetuses with isolated AAA, except for isolated RAA.

OCULO-AURICULO-VERTEBRAL SPECTRUM ASSOCIATED WITH ABERRANT SUBCLAVIAN ARTERY IN AN INFANT WITH RECURRENT RESPIRATORY DISTRESS

Objective:

To describe an infant with craniofacial microsomia and recurrent respiratory distress associated with aberrant right subclavian artery in order to review its most frequent congenital anomalies and alert the pediatrician to its rarer and more severe complications.

Case description:

This case report involves an 18-month-old male infant, only son of non-consanguineous parents. At birth, the child presented craniofacial dysmorphisms (facial asymmetry, maxillary and mandibular hypoplasia, macrostomia, grade 3 microtia, and accessory preauricular tag) restricted to the right side of the face. Additional tests showed asymmetric hypoplasia of facial structures and thoracic hemivertebrae. No cytogenetic or cytogenomic abnormalities were identified. The patient progressed to several episodes of respiratory distress, stridor, and nausea, even after undergoing gastrostomy and tracheostomy in the neonatal period. Investigation guided by respiratory symptoms identified compression of the esophagus and trachea by an aberrant right subclavian artery. After surgical correction of this anomaly, the infant has not presented respiratory symptoms and remains under multidisciplinary follow-up, seeking rehabilitation.

Comments:

Craniofacial microsomia presents a wide phenotypic variability compared to both craniofacial and extracraniofacial malformations. The latter, similarly to the aberrant right subclavian artery, is rarer and associated with morbidity and mortality. The main contribution of this case report was the identification of a rare anomaly, integrating a set of malformations of a relatively common condition, responsible for a very frequent complaint in pediatric care.

Prenatal Diagnosis of Aberrant Right Subclavian Artery: Association with Genetic Abnormalities

OBJECTIVE

 The objective of the present study was to determine the frequency of malformations and chromosomal abnormalities in a population of fetuses with an aberrant right subclavian artery (ARSA).

METHODS

 This is a 6-year retrospective study of fetuses with a prenatal diagnosis of ARSA conducted during the period between September 2013 and June 2019 at a fetal medicine unit. Data were collected from ultrasound, fetal echocardiograms, genetic studies, and neonatal records.

RESULTS

 An ARSA was diagnosed in 22 fetuses. An ARSA was an isolated finding in 18 out of 22 cases (82%). Associated abnormal sonographic findings were found in 4 cases. All cases underwent invasive testing. In 1 of the cases, a chromosomal abnormality was detected (mos 45,X [13]/46,X,e(X) (p22.1q22.1)). No cases of congenital heart disease were found in any of these fetuses. There were two cases in which the postnatal evaluation revealed a malformation: one case of hypospadias and 1 case of cleft palate.

CONCLUSION

 The presence of an isolated ARSA is benign and is not associated with chromosomal abnormalities. The finding of ARSA, however, warrants a detailed fetal ultrasound in order to exclude major fetal abnormalities and other soft markers.

Predictive value of aberrant right subclavian artery for fetal chromosome aneuploidy in women of advanced maternal age

Background

In the entire population, an aberrant right subclavian artery (ARSA) is closely associated with chromosomal abnormalities. ARSA with additional ultrasonic findings would increase risk of chromosomal abnormalities. The risk of fetal chromosomal abnormalities increased exponentially with the maternal age. These risks in the advanced maternal age (AMA) group are uncertain. This study aimed to determine the incidence of ARSA in Chinese AMA and non-AMA women and the frequency of aneuploidy among AMA and non-AMA women with ARSA.

Methods

This retrospective study included 13,690 singleton pregnancies, were divided into AMA and non-AMA groups. Integrated obstetric ultrasonic screening, biochemical screening, noninvasive prenatal screening, and fetal karyotype analysis were analyzed.

Results

The overall incidence of ARSA was 0.69%, with no difference between age groups. The incidence of chromosomal abnormalities in the AMA group (37 / 2860) was much higher than that of the non-AMA group. The risk of chromosomal abnormalities significantly increased with both ARSA detected and additional ultrasound findings. With combined ARSA and AMA, the likelihood of the incidence of chromosomal abnormalities increased. Chimerism (45X / 46XX) was found with isolated ARSA in AMA pregnancies.

Conclusion

There is a high prevalence of chromosomal abnormalities in fetuses of AMA women. ARSA increases the risk of chromosomal abnormalities in both age groups, especially combined with ARSA. When ARSA occurs in AMA women, it confers a high likelihood of chromosomal abnormalities.

Is it useful to evaluate the presence of aberrant right subclavian artery in prenatal diagnosis ultrasounds?

AIM

Analyze if the evaluation of aberrant right subclavian artery in the prenatal echography has improved the detection of chromosomal, genetic and/or morphological abnormalities in our population.

METHODS

Descriptive, observational, cross-sectional study of the cases of aberrant right subclavian artery diagnosed in our Prenatal Diagnosis Unit between January of 2011 and December of 2018.

RESULTS

Two hundred and fifty-seven cases of aberrant right subclavian artery were diagnosed and among them, 179 were considered isolated cases and thus were confirmed after birth. The detection of aberrant right subclavian artery did not improve itself neither the diagnosis of trisomy 21 in the second trimester of pregnancy nor other chromosomal or genetic abnormalities, including the not isolated cases. There were two cases of trisomy 21 diagnosed in the second trimester that presented major sonographic disorders and an inadequate examination during the first trimester. When aberrant right subclavian artery was associated with soft markers of aneuploidy in the second trimester, any case was a trisomy 21. Aberrant right subclavian artery seems to be associated with some minor and major heart defects, especially ventriculoseptal defect and aneurismatic ductus, and in some cases, also with clubfeet.

CONCLUSION

When an adequate screening of aneuploidies and a thorough ultrasound have been performed during the first trimester, aberrant right subclavian artery hardly helps to perform other diagnosis in the second trimester.

The “No ARSA” Sign: A Novel Method of Prenatal Screening for Aberrant Right Subclavian Artery

An aberrant right subclavian artery (ARSA) can be overlooked by the conventional method as described by Chaoui et al., due to acoustic shadowing. The aim of this study was to evaluate the feasibility and accuracy of a novel screening method for ARSA by demonstrating the brachiocephalic artery bifurcation, referred to as the “No ARSA” sign. A prospective study conducted at a tertiary care center between 2018 and 2019 included unselected pregnant patients at a median gestational age of 15.1 (14.2–22.1; IQR (inter-quartile range)) weeks, who had been referred for a routine or targeted anomaly scan. All participants were scanned for the presence or absence of ARSA using both the conventional and the novel “No ARSA” methods for validation purposes. A total of 226 unselected patients were enrolled in the study. The “No ARSA” sign was visualized in 218 fetuses (96.5%). In the remaining 8 cases (3.5%), the “No ARSA” sign was not demonstrated. In these fetuses, an ARSA was visualized by the conventional method. The new method exhibited 100% feasibility and was in complete agreement with the conventional method. Intra- and inter-observer agreement was excellent (κ = 1). The results of the study suggest that the “No ARSA” sign is an efficient and reliable screening tool for ARSA.

22q11.2 deletion syndrome and congenital heart disease

The 22q11.2 deletion syndrome has an estimated prevalence of 1 in 4-6,000 livebirths. The phenotype varies widely; the most common features include: facial dysmorphia, hypocalcemia, palate and speech disorders, feeding and gastrointestinal disorders, immunodeficiency, recurrent infections, neurodevelopmental and psychiatric disorders, and congenital heart disease. Approximately 60-80% of patients have a cardiac malformation most commonly including a subset of conotruncal defects (tetralogy of Fallot, truncus arteriosus, interrupted aortic arch type B), conoventricular and/or atrial septal defects, and aortic arch anomalies. Cardiac patients with a 22q11.2 deletion do not generally experience higher mortality upon surgical intervention but suffer more peri-operative complications than their non-syndromic counterparts. New guidelines suggest screening for a 22q11.2 deletion in the patient with tetralogy of Fallot, truncus arteriosus, interrupted aortic arch type B, conoventricular septal defects as well as those with an isolated aortic arch anomaly. Early identification of a 22q11.2 deletion in the neonate or infant when other syndromic features may not be apparent allows for timely parental screening for reproductive counseling and anticipatory evaluation of cardiac and noncardiac features. Screening the at-risk child or adult allows for important age-specific clinical, neurodevelopmental, psychiatric, and reproductive issues to be addressed.

Microarray analysis has no additional value in fetal aberrant right subclavian artery: description of 268 pregnancies and systematic literature review

OBJECTIVES

Fetal aberrant right subclavian artery (ARSA) is a relatively common sonographic finding. Several studies have reported a significant association between ARSA and Down syndrome, as well as 22q11.2 microdeletion. The objective of this study was to assess the risk of abnormal chromosomal microarray analysis (CMA) findings in a large cohort of pregnancies with fetal ARSA as an isolated, as well as a non-isolated, sonographic anomaly. A secondary objective was to review the literature, examining the frequency of chromosomal microarray aberrations in fetuses with isolated ARSA.

METHODS

Data from all pregnancies referred for invasive testing and CMA due to sonographic diagnosis of fetal ARSA, between 2013 and 2017, were obtained retrospectively from the computerized database of the Israeli Ministry of Health. The rate of clinically significant CMA findings in these fetuses was compared to that in a local control population of 2752 low-risk pregnancies with normal ultrasound and serum screening results. In addition, a literature search was conducted in PubMed, from inception to February 2018, of original studies in the English language describing the frequency and nature of microscopic and submicroscopic aberrations in fetuses with isolated ARSA.

RESULTS

Of 246 pregnancies with isolated ARSA that underwent CMA analysis, a clinically significant finding was detected in one (0.4%) pregnancy (trisomy 21). This rate did not differ significantly from that in the control population (P = 0.1574). Of 22 fetuses with non-isolated ARSA, one (4.5%) additional case of trisomy 21 was noted. The frequency of trisomy 21 in this cohort also did not differ from that in the control population (relative risk, 5.5 (95% CI, 0.8-37.6)). The literature search yielded 13 additional relevant papers, encompassing 333 cases of isolated ARSA. Of 579 cases overall (including those of the present study), 13 (2.2%) cases of trisomy 21 were detected, with no cases of 22q11.2 microdeletion.

CONCLUSION

While an association may exist between non-isolated ARSA and Down syndrome, isolated ARSA might better serve as a soft marker for Down syndrome, rather than a routine indication for invasive prenatal testing. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.