From the Hear

Israel (Y.R., M

University, Te

Reprint reque

Center of Isra

gmail.com).

0894-7317/$3

Copyright 201

http://dx.doi.o

Prenatal Diagnosis and Outcome of Right Aortic Archwithout Significant Intracardiac Anomaly

Yaron Razon, MD, Michael Berant, MD, Rami Fogelman, MD, Gabriel Amir, MD,and Einat Birk, MD, Petah-Tikva, Israel

Background: Right aortic arch (RAA) is usually associated with the presence of a significant congenital heartdisease, usually a conotruncal defect, which determines the postnatal outcome. In the absence of such car-diac defects, the significance of RAA has not been determined. The aims of this study were to evaluate thesignificance of recognizing RAA in fetuses with normal or near normal intracardiac anatomy and to determinewhich associations may be present.

Methods: A retrospective study was completed of all fetuses diagnosed with RAA with normal or near normalintracardiac anatomy between 1999 and 2011. The aim was to evaluate the presence of RAA with completeultrasonic evaluation using two-dimensional imaging complemented by the Doppler color flow technique,paying particular attention to the three-vessel and tracheal view. We compared the prenatal findings withthe postnatal outcomes and management of this cohort of fetuses.

Results: Among 16,450 fetal echocardiograms, 58 fetuses (0.35%) were diagnosed with RAA with normal ornear normal intracardiac anatomy. Gestational age at diagnosis ranged from 19 to 34weeks (mean, 23weeks).Isolated RAAswere found in 50 fetuses, and double aortic arches (DAAs) were recognized in eight other cases.The postnatal cohort consisted of 44 newbornswith RAAs and eight with DAAs (twowere lost to follow-up, andfour pregnancies were terminated). Postnatal echocardiography confirmed the prenatal diagnosis of RAA in41 of 45 children, and four were found to have DAAs. Three of seven fetuses diagnosed prenatally as havingDAAs were found to have only RAAs. Fourteen fetuses underwent karyotyping; two had 22q11 deletion andtwo had 47xxy. Eleven infants (21%) had respiratory symptoms, eight with DAAs, one with RAA, mirror-image head and neck vessels, and two with RAAs and aberrant left subclavian arteries. Surgery was indicatedin all symptomatic patients except one, whose symptoms resolved. One asymptomatic patient underwentoperation for significant compression of the trachea.

Conclusions: RAA on fetal ultrasonography may indicate vascular and chromosomal abnormalities that maycomplicate postnatal management. When RAA is identified, fetal karyotype analysis (including the integrityof chromosome 22) is warranted. RAA may herald an occult DAA and may be a clue to a tight vascular ring.Hence, it seems essential to conduct a careful postnatal evaluation of fetuses with RAAs on prenatalultrasound. (J Am Soc Echocardiogr 2014;-:---.)

Keywords: Echocardiography, Vascular ring, Fetal anomalies

Right aortic arch (RAA) is a congenital vascular anomaly present in0.086% to 0.1% of pregnancies.1,2 It usually accompanies othercongenital heart defects, most often tetralogy of Fallot (with orwithout pulmonary atresia).3 Nevertheless, in 25% of cases, it is pre-sent in association with normal or near normal intracardiac anat-omy.3,4 A vascular ring can most commonly be formed by a doubleaortic arch (DAA) or by RAA with a left-sided ductus connected toa diverticulum of Kommerell, giving rise to an aberrant left subclavian

t Institute, Schneider Children Medical Center of Israel, Petah-Tikva,

.B., R.F., G.A., E.B.); and the Sackler Faculty of Medicine, Tel Aviv

l Aviv, Israel (Y.R., M.B., R.F., G.A., E.B.).

sts: Yaron Razon, MD, Heart Institute, Schneider Children Medical

el, 14 Kaplan Street, Petah-Tikva 49202, Israel (E-mail: yrazon@

6.00

4 by the American Society of Echocardiography.

rg/10.1016/j.echo.2014.08.003

artery. Such vascular rings may lead to respiratory distress ordysphagia during infancy or later in life.5-8

With the development of high-resolution ultrasound, the aortic archcourse can nowbe identified prenatally. After birth, the prognosis of pa-tients with RAAs with congenital heart defects is usually determined bythe severity of the cardiac defects.3,4 The prognosis of patients withRAAs with normal cardiac anatomy, however, is determined byvascular compression of the trachea or esophagus, giving rise torespiratory symptoms or dysphagia.5 The purpose of the present studywas to determine how the prenatal diagnosis of RAA with normal ornear normal intracardiac anatomymight focus attention on appropriatepostnatal management and treatment, thus improving outcomes.

METHODS

We performed a retrospective review of all fetal ultrasound studies atour institution between 1999 and 2011 and found 16,450 patientswho had undergone fetal echocardiography.

1

Abbreviations

DAA = Double aortic arch

RAA = Right aortic arch

VSD = Ventricular septal

defect

2 Razon et al Journal of the American Society of Echocardiography- 2014

Fetuses with normal or nearnormal intracardiac anatomy,diagnosed as having RAA aloneor as part of a DAA wereenrolled in the study. We didinclude fetuses and newbornswith mild intracardiac lesionsthat do not have hemodynami-

Figure 1 (Top) This figure shows the normal position of theaortic arch in the three-vessel view in a fetus at 28 weeks’ gesta-tion. The superior vena cava (SVC) is noted on the right. Theaortic arch (Ao A), the pulmonary artery (PA), and the ductus ar-teriosus (Duct) are identified sequentially from right to left, asindicated on the figure. The aortic arch runs to the left of the tra-chea (Trach). The vertebral spine is also indicated, as are theright and left laterality markers. (Bottom) Doppler color flow im-age from the same fetus showing the directionality of flow inboth the aortic and ductal and confirming the vascular struc-tures to the left of the trachea.

cally significant consequences, such as small ventricular septal defects(VSDs), bicuspid aortic valve, and left superior vena cava draining tothe coronary sinus.

All patients underwent complete transabdominal fetal ultrasoundstudies using an Acuson Sequoia 512 ultrasound system (SiemensMedical Solutions USA, Inc, Mountain View, CA). The aortic archand tracheawere imaged in a transverse view of the fetal upper thorax(the three-vessel and tracheal view). The images were complementedwith Doppler color flow imaging to enhance the morphologic infor-mation and to assess flow direction. Special attention was paid tothe Nyquist scale, lowering it to levels appropriate to detect fetalblood flow. At this tomographic plane, the transverse aorta, pulmo-nary artery, superior vena cava, and trachea are demonstrated. Inthe normal heart, the pulmonary trunk is the largest andmost anteriorand leftward vessel, and the superior vena cava is the smallest mostposterior and rightward vessel. The transverse aorta lies betweenthese vessels to the left of the trachea, recognized as a circular struc-ture with an echogenic wall and an echo-free lumen anterior to thespine (Figure 1). When RAA is present, the transverse aorta lies tothe right of the trachea (Figure 2).1,9-12 When an anomalous leftsubclavian artery is noted, its origin is noted to arise from thedescending aorta, and it runs behind the trachea and to the left ofthe region where the left ductus and aorta join (Figure 3). In thecase of DAA, it was possible to recognize the components of thearch surrounding the trachea (Figure 4).

We noted gestational age at the time of the fetal ultrasound study.We offered chromosomal analysis to all women who were examinedto evaluate chromosomal anomalies. We evaluated the postnatalrecords, including surgical reports, of this cohort, noting the clinicalfindings, presence or absence of respiratory symptoms, and echocar-diographic findings. We also assessed the magnetic resonance orcomputed tomographic x-ray reports and bronchoscopy reports, ifthe pulmonologist decided that they were appropriate. We also con-tacted all nonsurgical patients by phone to assess their well-being.

Statistical analysis was performed bymeans of two-by-two tables toassess sensitivity, specificity, and positive and negative predictivevalues. All pertinent patient data were recorded on a spreadsheetand made anonymous. Our institutional ethics committee approvedthe study.

RESULTS

We performed 16,450 complete fetal cardiac ultrasonic examinationsbetween 1999 and 2011. RAAs with normal or near normal intracar-diac anatomy were noted in 58 fetuses (0.35%). The mean gesta-tional age was 22.7 weeks (range, 19–34 weeks; median,22 weeks). Mean follow-up time after birth was 49 months (range,17–112 months; median, 40 months).

There were 58 fetuses prenatally suspected to have RAAs, eight ofwhom were suspected to have DAAs (Figure 5; Table 1).

Among the group of 50 fetuses with RAAs, 37 had been referredwith that diagnosis. Three of the 50 were referred for DAAs, and 10

were referred for other reasons, such as family history or non-conotruncal-associated heart defects. In this group, four pregnancieswere terminated because of chromosomal anomalies, and one pa-tient was lost to follow-up, leaving 45 postnatal records availablefor evaluation after birth. Postnatal echocardiography confirmed theprenatal diagnosis of RAA in 41 of 45 children, and four were foundto have DAAs.

From the group of eight fetuses with DAAs, five were referredfor diagnosis of RAA, and three were referred for other reasons.One patient was lost to follow-up, leaving seven postnatal recordsavailable for evaluation after birth. Three of the fetuses diagnosedprenatally as having DAAs were found to have only RAAs(Figure 6).

For 56 fetuses, information about the sidedness of the ductus arte-riosus was available; only four fetuses (7%) had right ductus arteriosus(Table 1). A right ductus arteriosus does not complete a vascular ring,and all four fetuses were eventually asymptomatic after birth.

Only 14 fetuses underwent karyotype analysis, including fluores-cence in situ hybridization analysis for 22q11 deletion, because ofparental religious and cultural preferences. Two had chromosome

Figure 2 (Top) Image from patient 46 showing the presence ofRAA. Here the superior vena cava (SVC) lies adjacent to theRAA (R Ao A). The trachea lies to the left of and adjacent tothe aorta. The ductus runs posteriorly and is in continuity withthe pulmonary artery (PA). The vertebral spine is also indicated,as are markers of right and left laterality. (Bottom) Doppler colorflow image from the same fetus showing the directionality offlow and confirming the aorta to the right of the trachea withthe ductus coursing posteriorly and joining the main pulmonaryartery.

Figure 3 (Top) Image frompatient 33 showing the trachea, iden-tified by an arrow, and the RAA (R Ao A). An anomalous left sub-clavian artery (LSA) is seen arising from the arch. The left carotidartery (L Carotid) is also identified. The superior vena cava (SVC)lies to the right of the aortic arch. The vertebral spine is also indi-cated, as are markers of right and left laterality. (Bottom) Imagefrom patient 39, showing a Doppler color flow image of the RAAand anomalous left subclavian artery. The trachea is identifiedby an arrow, and the RAA (R Ao A) runs to the right of it. Ananomalous left subclavian artery (An. LSA) with red flow isseen arising from the arch. The ductus (Duct) and the pulmonaryartery (PA) complete the vascular ring.

Journal of the American Society of EchocardiographyVolume - Number -

Razon et al 3

22q11 deletion, and two had 47xxy, and in all four cases, the parentselected to terminate the pregnancies. One additional infant (patient57 in Table 1), who did not have prenatal chromosomal analysis,was found to have 22q11 deletion after birth. In total, therefore,five of 58 patients (9%) had RAAs and also had chromosomal anom-alies.

The postnatal cohort consisted of 44 patients with RAAs and eightpatients withDAAs. Identifying RAAs in fetuses had high sensitivity of93% but lower specificity of 50%. Fetal diagnosis of DAA had lowsensitivity of 50%, but the specificity was 93% (Tables 2 and 3;Figure 6).

Aberrant left subclavian arteries were recognized in 23 patients. In18 patients they were recognized on fetal ultrasound, and in five pa-tients they were diagnosed after birth by echocardiography or tomo-graphic imaging; the presence or absence of aberrant left subclavianartery was not recorded in the other cases and could not be retrievedby reviewing the studies. A certain diagnosis of RAA with

mirror-image branching of the head and neck vessels was made inonly one patient by tomographic imaging (patient 45 in Table 1),before surgery.

Seven patients had mild intracardiac lesions of no hemodynamicsignificance. These included five patients with small muscular VSDs(three diagnosed on fetal echocardiography), one with a small peri-membranous VSD, one with a bicuspid aortic valve, and two withleft superior vena cavae draining to the coronary sinus (one diagnosedon fetal echocardiography). One of these patients is included twicebecause the patient had both a small muscular VSD and a left superiorvena cava–to–coronary sinus connection (Table 1).

After birth, 11 patients were found to have respiratory symptoms(21%). Ten patients were symptomatic with stridor during infancy,while one of the patients became symptomatic at 3.5 years of age.Eight had DAAs, and two had RAAs with an aberrant left subclavianarteries and Kommerell diverticulum. One had RAA with mirror-

Figure 4 (Top) Image from patient 9, showing the features of aDAA with the larger RAA (R Ao A) and smaller left aortic arch (LAo A) encircling the trachea. The superior vena cava (SVC) liesto the right of the aortic arch. The vertebral spine is also indicated,as are markers of right and left laterality. (Bottom) Image frompatient 42, showing Doppler color flow imaging of the DAA encir-cling the trachea (unlabeled). The smaller left aortic arch (L Ao A)shows flow in red, and the dominant right arch (R Ao A) showsflow in blue. The ductus (Duct) completes the vascular ring. Thesuperior vena cava (SVC) lies to the right of the aortic arch. Thepulmonary artery (PA) is also labeled. The vertebral spine isalso indicated, as are the right and left laterality markers.

Figure 5 Fetal cardiac ultrasound results and enrollment. Thisfigure is a flowchart showing the follow-up of the 58 fetalpatients.

4 Razon et al Journal of the American Society of Echocardiography- 2014

image head and neck vessels, with a left ligamentum arteriosum to thedescending aorta (forming the vascular ring).

Ten of the 11 symptomatic patients underwent surgery, while inone patient with RAA and an aberrant left subclavian artery, thesymptoms resolved, and the patient did not require surgery. One pa-tient with RAA and an aberrant left subclavian artery did not have sig-nificant respiratory symptoms but underwent surgery for significantcompression of the trachea with tracheomalacia on bronchoscopyand magnetic resonance imaging. Eleven patients in total underwentsurgery (21%) for vascular ring, eight patients with DAAs and threewith RAAs (Table 4).

DISCUSSION

Previous studies that described RAA in the fetus mixed patients bothwith andwithout structural heart disease.3,4,12,13We sought to identify

whether RAA without significant structural heart disease is a markerof fetal abnormality and may influence postnatal outcomes.

We found that 0.35% of our fetal population had RAAs withoutsignificant structural heart disease. Our prevalence is higher thanthose found in other studies, in which prevalence ranged from0.05% to 0.02%.1,13-16 This increased frequency probably relates totwo factors: ours is a single large referral center, and our referringphysicians are familiar with the ultrasonic recognition of RAA.

RAA, although readily recognizable, may be a part of a vascularring created by a left ductus arteriosus and anomalous subclavian ar-tery with a Kommerell diverticulum, or by a DAA. In our series, fourpatients, recognized as having RAAs on fetal echocardiography, werefound after birth to have DAAs. It is a challenge to differentiate be-tween RAA and DAA in the fetus, as demonstrated by previous re-ports as well.3,11,13 The diagnosis hinges on correctly identifying thebrachiocephalic arterial branching pattern. DAA is defined by theorigins of one carotid and one subclavian artery from each arch. Ontransverse view, the vascular ring of DAA encircles the fluid-filled tra-chea and can be imaged in a single imaging plane, giving rise to theappearance of a figure of six or a figure of nine (Figure 4).11 It is some-times impossible to recognize the complete vascular ring of a DAAprenatally when the subordinate arch is fibrotic and undetectableby ultrasound or tomographic imaging means.

Postnatal respiratory symptoms, the most common symptom lead-ing to diagnosis and referral for surgery in patients with vascular ringspostnatally,8,15 appeared in 21% of our cohort (11 of 52). After birth,our patients could be divided into two distinct groups: those withDAAs, all of whom had prominent symptoms and underwentsurgery (eight of eight), whereas those with RAAs alone had only a7% (three of 44) risk for having symptoms and undergoing surgery.Because of the difficulty of recognizing the complete vascular ring

Table 1 Prenatal and postnatal finings and outcomes of patients with RAA

Patient

Gestational

age (wk)

Referral

reason

Fetal

echocardiographic

findings

Additional

prenatal

findings

Ductus

arteriosus

Postnatal

echocardiography

Postnatal

findings

Additional

postnatal

findings Symptoms Surgery

1 23 RAA RAA ND Yes DAA Yes Yes2 21 RAA RAA Right Yes RAA BAV

3 27 RAA RAA ND Lost4 19 RAA RAA Left Yes RAA

5 21 DAA RAA Left Yes RAA6 26 RAA RAA Left Yes RAA

7 22 RAA RAA ABLS Left Yes RAA8 34 RAA RAA Right Yes RAA

9 32 Mother

with DAA

DAA Left Yes DAA Stridor Yes

10 21 RAA RAA Left Yes DAA Stridor Yes

11 21 RAA RAA Left Yes RAA Musc VSD Stridor12 25 RAA RAA ABLS + VSD Left Yes RAA Musc VSD

13 30 RAA RAA Left Yes RAA14 27 RAA RAA ABLS Left Yes RAA

15 22 Single UA RAA Left Yes DAA Atretic

left arch

Yes Yes

16 22 Siblingwith VSD

RAA Left Yes RAA ABLS Stridor Yes

17 23 RAA DAA Left Yes RAA ABLS18 20 Husband with

murmur

RAA 22q11

deletion

Left TOP

19 26 Suspected TA RAA Left Yes DAA Stridor Yes

20 19 RAA RAA ABLS Left Yes RAA PM VSD

21 25 RAA RAA 22q11

deletion

Left TOP

22 26 RAA RAA Left Yes RAA

23 26 Single UA RAA Left Yes RAA ABLS24 21 RAA RAA ABLS + left

SVC to CS

Left Yes RAA Musc VSD left

SVC to CS

25 20 RAA RAA 47xxy Left TOP26 31 ND RAA Right Yes RAA

27 23 ND RAA Left Yes RAA ABLS left

SVC to CS

28 22 Axis deviation RAA Left Yes RAA ABLS

29 22 RAA RAA Left Yes RAA30 20 ND RAA Left Yes RAA

31 23 DAA RAA Left Yes RAA ABLS32 23 VSD RAA VSD Right Yes RAA Musc VSD No

33 20 RAA RAA ABLS Left Yes RAA34 22 RAA RAA Left Yes RAA

35 25 DAA RAA ABLS Left Yes RAA ABLS36 27 RAA RAA ABLS Left Yes RAA ABLS

37 20 RAA RAA ABLS Left Yes RAA ABLS38 21 RAA DAA Left Yes DAA Yes Yes

39 19 RAA RAA ABLS Left Yes RAA ABLS40 23 RAA RAA ABLS, 47xxy Left TOP

41 20 RAA RAA ABLS Left Yes RAA ABLS42 22 RAA DAA Left Yes DAA Stridor Yes

43 21 RAA RAA ABLS Left Yes RAA ABLS Yes

44 21 RAA RAA ABLS Left Yes RAA ABLS

45 22 RAA RAA Left Yes RAA Stridor,

dysphagia

Yes

46 24 RAA RAA ABLS Left Yes RAA ABLS

47 24 Twins DAA Left Lost48 21 RAA DAA Left Yes RAA ABLS

(Continued )

Journal of the American Society of EchocardiographyVolume - Number -

Razon et al 5

Table 1 (Continued )

Patient

Gestational

age (wk)

Referral

reason

Fetal

echocardiographic

findings

Additional

prenatal

findings

Ductus

arteriosus

Postnatal

echocardiography

Postnatal

findings

Additional

postnatal

findings Symptoms Surgery

49 19 RAA RAA Left Yes RAA ABLS50 26 RAA DAA Left Yes RAA ABLS

51 23 RAA RAA Left Yes RAA52 22 RAA RAA ABLS Left Yes RAA ABLS

53 21 RAA RAA Left Yes RAA ABLS54 21 RAA RAA ABLS Left Yes RAA ABLS

55 23 RAA RAA Left Yes RAA56 21 RAA RAA VSD Left Yes RAA Musc VSD

57 20 RAA RAA Left Yes RAA 22q11 deletion58 21 ND DAA Left Yes DAA Stridor Yes

ABLS, Aberrant left subclavian artery;BAV, bicuspid aortic valve;CHF, congestive heart failure;CS, coronary sinus; LAA, left aortic arch; Lost, lostto follow-up;Musc, muscular;ND, no data;PM, perimembranous;SVC, superior vena cava; TA, truncus arteriosus; TOP, termination of pregnancy;

UA, umbilical artery.

Figure 6 Postnatal courses and outcomes. This figure is a flow-chart showing the postnatal course and outcomes of the 52 pa-tients whom we were able to follow.

Table 2 Sensitivity and specificity of the diagnosis of RAA

RAA DAA Total 95% CI

Ultrasound RAA 41 4 45 Sensitivity 93.2% 93.5%–81.3%

Ultrasound DAA 3 4 7 Specificity 50% 84%–16%

Total 44 8 PPV 91.1% 94.5%–78.8%

NPV 57.1% 18.7%–89.6%

CI, Confidence interval;NPV, negative predictive value;PPV, positive

predictive value.

Table 3 Sensitivity and specificity of the diagnosis of DAA

DAA RAA Total 95% CI

Ultrasound DAA 4 3 7 Sensitivity 50% 16%–84%

Ultrasound RAA 4 41 45 Specificity 93% 81.3%–98.5%

Total 8 44 PPV 57.1% 18.7%–89.6%

NPV 91.1% 78.7%–97.5%

CI, confidence interval;NPV, negative predictive value; PPV, positive

predictive value.

6 Razon et al Journal of the American Society of Echocardiography- 2014

of a DAA, it should be emphasized to parents that a DAA cannot beexcluded when RAA is seen on fetal ultrasound. When RAA wasfound on fetal ultrasound, therefore, the risk for postnatal surgeryin our series was 21%. RAA with right ductus arteriosus does notform a complete vascular ring, because the left side of the ring (theleft ductus ligament) is absent. In our series, the prevalence of rightductus arteriosus was low: only four patients with right ductus

arteriosus were found (7%). As expected, all four wereasymptomatic after birth.

RAA may be the only cardiac manifestation of DiGeorge syn-drome (chromosome 22q11 deletion).16 Chromosomal analysiswas possible in this series in only 14 fetuses and in one patient afterbirth. Of these, three were positive for chromosome 22q11 deletion.Finding additional chromosomal abnormalities, 47xxy (Klinefelter’ssyndrome) in two chromosomal studies was surprising, as this associ-ation has not been previously reported. There is one case report of achild with DAA and chromosomal anomaly of 48xxy+21.17

We had an incidence of chromosomal abnormalities of $9%(assuming all other fetuses were normal) and $5% incidence of22q11 deletion. Ourmeta-analysis of the data of Zidere et al.3 showedan 8% prevalence of chromosome 22q11 deletion in their series ofpatients with prenatal diagnosis of isolated RAA. McElhinney et al.18

studied the presence of chromosome 22q11 deletion in a large groupof patients with normal hearts and different arch anomalies. They

Table 4 Arch anatomy, symptoms, and age at surgery

Patient

(from Table 1) Anatomy Symptoms

Age at

surgery

1 DAA Stridor 4 mo

9 DAA Stridor 8 mo

10 DAA Stridor 7 mo

15 DAA (left

atretic arch)

Respiratory symptoms

(appeared at age 3 y)

3.5 y

16 RAA-ABLS Stridor 6 mo

19 DAA Stridor 6 mo

38 DAA Stridor 4 mo

42 DAA Stridor 2.5 mo

43 RAA-ABLS None 20 mo

45 RAA Stridor, dysphagia 14 mo

58 DAA Stridor 2 mo

ABLS, Aberrant left subclavian artery.

Journal of the American Society of EchocardiographyVolume - Number -

Razon et al 7

found an even higher prevalence of 22q11 deletion of 22% in a sub-set similar to our patients (i.e., RAAwithout stenosis or atresia of pul-monary arteries).

Limitations

The main limitation of our study is that it was retrospective. Imagingtechniques and the examiners’ experience improved with time; weuse 6- and 8-MHz probes now, compared with a 5-MHz probe atthe beginning of the period, improving the quality of imaging. It ispossible that some patients with RAAs and normal cardiac anatomywere missed during the earlier period, as described in previous retro-spective studies.2 In addition, the presence or absence of an aberrantleft subclavian artery was not consistently recorded. RAA with a leftsubclavian artery arising from a left innominate artery and a ductus ar-teriosus arising from the base of this innominate artery (mirror-imageRAA5) does not create a vascular ring. Thus, prenatal diagnosis of thepresence or absence of an aberrant left subclavian artery is important.Our population had a referral bias, and most of our examinationswere done because of suspicion of RAA or DAA by the gynecologist;that could explain the high prevalence of arch anomalies. Because ofregional, religious, and cultural preferences, we conducted a smallnumber of prenatal chromosomal analyses, and only one additionalpatient underwent chromosomal analysis after birth. This couldhave led to an underestimation of the incidence of chromosomal ab-normalities in these patients.

CONCLUSIONS

The presence of RAA on fetal ultrasonography is an important markerof the presence of vascular abnormalities and chromosomal problemsthat may complicate postnatal management. When RAA is diagnosedin a fetus, karyotype, including the integrity of chromosome 22,should be examined. The presence of RAA may herald the presence

of an occult DAA. Postnatal assessment of fetuses recognized to haveRAAs seems to be essential.

REFERENCES

1. Achiron R, Rotstein Z, Heggesh J, Bronshtein M, Zimand S, Lipitz S, et al.Anomalies of the fetal aortic arch: a novel sonographic approach to in-utero diagnosis. Ultrasound Obstet Gynecol 2002;20:553-7.

2. Li S, Luo G, Norwitz ER, Wang C, Ouyang S, Yao Y, et al. Prenataldiagnosis of congenital vascular rings and slings: sonographic featuresand perinatal outcome in 81consecutive cases. Prenat Diagn 2011;31:334-46.

3. Zidere VE, Tsapakis GI, Huggon C, Allan LD. Right aortic arch in the fetus.Ultrasound Obstet Gynecol 2006;28:876-81.

4. Berg C, Bender F, SoukupM, Geipel A, Axt-Fliedner R, Breuer J, et al. Rightaortic arch detected in fetal life. Ultrasound Obstet Gynecol 2006;28:882-9.

5. Weinberg PM, Aortic arch anomalies 707–735. InMoss andAdams, Heartdisease in infants, children, and adolescent, Sixth edition, volume II.

6. Knight L, Edwards JE. Right aortic arch – types and associated anomalies.Circulation 1974;50:1047-51.

7. McElhinney DB, Hoydu AK, Gaynor JW, Spray TL, Goldmuntz E,Weinberg PM. Patterns of right aortic arch and mirror-image branchingof the brachiocephalic vessels without associated anomalies. Pediatr Car-diol 2001;22:285-91.

8. Roesler M, De Leval M, Chrispin A, Stark J. Surgical management ofvascular ring. Ann Surg 1983;197:139-46.

9. Yagel S, Arbel R, Anteby EY, Raveh D, Achiron R. The three vessels andtrachea view (3VT) in fetal cardiac scanning. Ultrasound Obstet Gynecol2002;20:340-5.

10. Lee H, Roman K, Jaeggi E, Smallhorn J. Fetal sonographic diagnosis ofaortic arch anomalies. Ultrasound Obstet Gynecol 2003;22:535-46.

11. Yoo SJ, Min JY, Lee YH, Roman K, Jaeggi E, Smallhorn J. Fetal sonographicdiagnosis of aortic arch anomalies. Ultrasound Obstet Gynecol 2003;22:535-46.

12. Jain S, Kleiner B, Moon-Grady A, Hornberger LK. Prenatal diagnosis ofvascular rings. J Ultrasound Med 2010;29:287-94.

13. Galindo A, Nieto O, Nieto MT, Rodr�ıguez-Mart�ın MO, Herraiz I,Escribano D, et al. Prenatal diagnosis of right aortic arch: associated find-ings, pregnancy outcome, and clinical significance of vascular rings. PrenatDiagn 2009;29:975-81.

14. Tuo G, Volpe P, Bava GL, Bondanza S, De Robertis V, Pongiglion G, et al.Prenatal diagnosis and outcome of isolated vascular ring. Am J Cardiol2009;103:416-9.

15. Alsenaidi K, Gurofsky R, Karamlou T, WilliamsWG, McCrindle BW. Man-agement and outcomes of double aortic arch in 81 patients. Pediatrics2006;118:e1336-41.

16. McElhinneyDB, McDonald-McGinnD, Zackai EH, Goldmuntz E. Cardio-vascular anomalies in patients diagnosed with a chromosome 22q11 dele-tion beyond 6 months of age. Pediatrics 2001;108:e104.

17. GerretsenMF, PeelenW, Rammeloo LA, KoolbergenDR, Hruda J. Doubleaortic arch with double aneuploidy—rare anomaly in combined Down andKlinefelter syndrome. Eur J Pediatr 2009;168:1479-81.

18. McElhinney DB, Clark BJ 3rd, Weinberg PM, Kenton ML, McDonald-McGinn, Driscoll DA, et al. Association of chromosome 22q11 deletionwith isolated anomalies of aortic arch laterality and branching. J Am CollCardiol 2001;37:2114-9.