Patterns of right aortic arch and mirror-image branching of the brachiocephalic vessels without associated anomalies

[Prenatally detected aortic arch anomalies and their consequences after birth]

INTRODUCTION

Aortic arch anomalies are frequently associated with cardiac or extracardiac malformations, chromosomal aberrations and postpartum esophagus/trachea compression.

OBJECTIVE

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.

METHOD

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.

RESULTS

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.

CONCLUSION

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.

Prenatal Diagnosis of the Right Aortic Arch: Change in Detection Rate, the Status of Associated Anomalies, and Perinatal Outcomes in 137 Fetuses

To evaluate prenatal findings of the right aortic arch (RAA), associated cardiac, extracardiac, and genetic anomalies, its perinatal outcomes and the need for postnatal interventions in cases of isolated RAA with a view to facilitating appropriate counseling. This was a multicenter, cohort study, that was undertaken in two international major cardiac centers between 2009 and 2020. The study subjects were prenatally diagnosed RAA cases with and without other structural cardiac defects. A RAA was identified in 137 fetuses. There were 84 cases of isolated RAA. Associations with additional intracardiac malformations were found in 53 (38.7%) cases. An extracardiac anomaly was observed in 26/137 (18.9%) fetuses, 11/84 (13.0%) fetuses with isolated RAA, and 15/53 (28.3%) fetuses with an additional intracardiac anomaly. The incidence of extracardiac and chromosomal anomalies was significantly higher in cases of RAA with abnormal intracardiac anatomy (28.3-18.8%, respectively), compared with RAA with normal intracardiac anatomy (13.0-5.9%, respectively) (p < 0.05). 22q11.2 microdeletion was found higher in RAA with CHD (4/18 fetuses) than isolated RAA (2/24 fetuses) (22.2% vs. 8.3% respectively). ALSA was present in 19.3% of cases. ALSA was more frequently observed in cases of isolated RAA (23.6%), than in RAA with structural CHD (7.6%) (p < 0.05). The pregnancy was interrupted in six fetuses, and one died in utero. The mortality rate was higher in fetuses with intracardiac anomaly than RAA without cardiac anomaly (11/49 (22.4%) vs. 2/81 (2.4%). Vascular ring formation was revealed in 21/98 cases. The RAA caused symptoms of a vascular ring in only one patient (0.7%) requiring surgery in the follow-up. Overall survival after initial diagnosis in the total cohort was 85.4% with 38 of 53 (71%) RAA with CHD cases and 79 of 84 (94.0%) isolated RAA cases. Chromosomal and extracardiac anomalies are lower in isolated RAA but not negligible hence amniocentesis should be routinely offered in all cases. The requirement for postnatal intervention in the immediate neonatal period is remote, therefore delivery of these fetuses need not be undertaken at a cardiac or surgical center.

Aortic Arch Variants and Anomalies: Embryology, Imaging Findings, and Clinical Considerations

There is a wide spectrum of congenital anomalies or variations of the aortic arch, ranging from non-symptomatic variations that are mostly detected incidentally to clinically symptomatic variations that cause severe respiratory distress or esophageal compression. Some of these may be accompanied by other congenital heart diseases or chromosomal anomalies. The widespread use of multidetector computed tomography (CT) in clinical practice has resulted in incidental detection of several variations of the aortic arch in adults. Thus, radiologists and clinicians should be aware of the classification of aortic arch anomalies and carefully look for imaging features associated with a high risk of clinical symptoms. Understanding the embryological development of the aortic arch aids in the classification of various subtypes of aortic arch anomalies and variants. For accurate diagnosis and precise evaluation of aortic arch anomalies, cross-sectional imaging modalities, such as multidetector CT or magnetic resonance imaging, play an important role by providing three-dimensional reconstructed images. In this review, we describe the embryological development of the thoracic aorta and discuss variations and anomalies of the aortic arch along with their clinical implications.

The multiform sonographic spectrum of arterial duct in right aortic arch

To study the different characteristics of arterial duct (AD) in a series of prenatally detected right aortic arch (RAA). Out of 832 congenital heart diseases (CHD) referred to a tertiary center, 98 cases had RAA. Based on anatomical landmarks we identified 7 types of AD: type 1 left-sided, transverse; type 2 left-sided, vertical; type 3 from the underside of aortic arch (AA), vertical; type 4 right-sided, mirror-image “V”, transverse; type 5 right-sided, “H” shaped, transverse; type 6 bilateral; type 7 absent or unidentifiable. For each type of AD the incidence of associated major CHD was calculated and chi-square test was applied to verify the null hypothesis with significance level of p < 0.05. Type 1 occurred in 43% of cases including 4 with CHD and no cases with pulmonary outflow obstruction (POO). Symptoms of vascular ring were present in 41% of survivors. Type 2, 3 and 7 AD were associated with tetralogy of Fallot (TOF) or equivalents. No type 5 AD with CHD had POO and 3 isolated cases had asymptomatic hypoplasia of left pulmonary artery (LPA). Two type 6 AD had disconnection of LPA. Type 1 occurred more often as an isolated finding (p < 0.001), whereas types 2 (p = 0.0026), 3 (p = 0.0045), 4 (p = 0.0325) and 7 (p = 0.0001) were frequently associated with major CHD. In RAA, type 1 (U-shaped) is usually an isolated finding (p < 0.001) which includes all symptomatic vascular rings. POO is always present when the AD is vertical or absent but not when it lies on a transverse plane. Bilateral AD is rare and brings the risk of functionary loss of left lung if not identified.

Right aortic arch with mirror image branching accompanied by absent pulmonary valve syndrome and tricuspid stenosis: Prenatal echocardiographic diagnosis of an unusual congenital heart defect

Right aortic arch (RAA) with mirror image branching (RAMI) accompanied by absent pulmonary valve syndrome (APVS), tricuspid stenosis, and hypoplastic right ventricle is an extremely rare combination of congenital heart anomalies. This combination might result in severe cardiac failure and respiratory compromise, indicating a poor prognosis. Here, we describe a detailed prenatal echocardiographic diagnosis of RAMI accompanied by APVS and tricuspid stenosis. These anomalies were further confirmed by autopsy. This case could be helpful in improving our understanding of this abnormal combination and the development of an early therapeutic strategy.

Prenatal echocardiographic assessment of right aortic arch

OBJECTIVES

To report our experience with fetal diagnosis of right aortic arch (RAA) variants based on the ductus arteriosus (DA) anatomy and brachiocephalic vessel branching pattern in relation to the trachea, and to establish whether the echocardiographic 'V-shaped' or 'U-shaped' appearance of the junction between the DA and aortic arch (AA) in the fetal upper mediastinal view is sufficiently accurate for assessment of fetal AA anatomy.

METHODS

This was a retrospective study of pregnancies with a prenatal diagnosis of fetal RAA that had postnatal confirmation of AA anatomy, referred to our tertiary center during 2011-2017. Prenatal and postnatal medical records, including echocardiographic and computed tomography (CT)/magnetic resonance imaging (MRI) scan reports, were reviewed, and cardiac and extracardiac abnormalities and the results of genetic testing were recorded.

RESULTS

Of 55 consecutive pregnancies with a prenatal diagnosis of fetal RAA, six were lost to follow-up, one was terminated and three were excluded due to lack of postnatal confirmation of AA anatomy. Of the remaining 45 pregnancies, AA anatomy was assessed postnatally by CT in 39, by MRI in one and by direct examination at cardiac surgery in five. A U-shaped appearance was found in 37/45 (82.2%) patients, all of which had a complete vascular ring (CVR). Of these 37 patients, on postnatal confirmation, 21 (56.8%) had RAA with Kommerell's diverticulum, left posterior ductus arteriosus (LPDA) and aberrant left subclavian artery (ALSA) (RAA/LPDA/ALSA), 11 (29.7%) had a double AA (DAA), four (10.8%) had RAA with Kommerell's diverticulum, LPDA and mirror-image (MI) branching (RAA/LPDA/MI), and one (2.7%) had RAA with Kommerell's diverticulum, LPDA and aberrant left innominate artery (ALIA) (RAA/LPDA/ALIA). A V-shaped appearance was found in 3/45 (6.7%) patients, all of which had RAA with right DA not forming a CVR and MI branching. In the 5/45 (11.1%) fetuses with neither U- nor V-shaped appearance, RAA with left anterior DA arising from the left innominate artery and MI branching, not forming a CVR, was found. Twelve (26.7%) fetuses had a congenital heart defect (CHD). RAA forming a CVR (U-shaped appearance) was associated with a septal defect in 6/37 (16.2%) fetuses, while RAA not forming a CVR (V-shaped appearance or no U- or V-shaped appearance) was associated with major CHD in 6/8 (75.0%) fetuses.

CONCLUSIONS

In fetuses with RAA, V-shaped appearance of the junction between the DA and AA indicates only that the transverse AA and DA run together on the same side of the thorax (trachea) while a U-shaped appearance is always a sign of a CVR. Among fetuses with a CVR, RAA/LPDA/MI is more frequent than described previously. Finally, RAA forming a CVR is not usually associated with complex CHD, as opposed to RAA not forming a CVR. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Left subclavian artery stenosis treated with transcatheter stent placement in pediatric patients

Left subclavian artery (LSA) stenosis causing limb length shortening or vascular compromise or significant pulse volume and blood pressure differences between two upper limbs are rarely described in pediatric patients. Here, we are presenting three such cases, two of them were congenital and another one acquired in origin. All of them were successfully treated with transcatheter implantation of stent in LSA. Normalization of limb length was detected on follow-up.

Methodology of echocardiographic analysis of morphological variations of the aortic arch and its branches in children - own experience

We wish to share our experience in echocardiographic assessment of the course of the aortic arch, illustrating it with multiple examples of the majority of possible variants. The course of the aortic arch and its branches may be visualized using high parasternal and suprasternal views in sagittal and transverse planes. It is hardly ever possible to visualize the entire aortic arch on a single ultrasonographic section, particularly in the case of pathological variations. Echocardiography should be performed in a dynamic mode, as in the case of CT angiography or magnetic resonance, by gradually moving the ultrasound beam and following the position of subsequent aortic segments and branches on the screen. Due to disturbances in ultrasound propagation caused by air-containing tissues, such as the trachea, bronchi and lungs as well as bones (sternum and ribs), each evaluation of the entire arch requires the use of a higher number of echocardiographic views. The presented data show that echocardiographic detection of the main details of aortic arch anomalies is possible in practically all cases. In the case of patients considered for surgical treatment, all unresolved issues should be clarified with CT angiography or MRI, enabling 3 dimensional reconstruction of vessels and other thoracic structures. Knowledge of the main elements of an abnormal arch is crucial for proper planning of this type of examination; therefore the diagnostic process should be always initiated with echocardiography. Echocardiography is often sufficient to answer all clinical questions and finalize the diagnostic process.

We wish to share our experience in echocardiographic assessment of the course of the aortic arch, illustrating it with multiple examples of the majority of possible variants. The course of the aortic arch and its branches may be visualized using high parasternal and suprasternal views in sagittal and transverse planes. It is hardly ever possible to visualize the entire aortic arch on a single ultrasonographic section, particularly in the case of pathological variations. Echocardiography should be performed in a dynamic mode, as in the case of CT angiography or magnetic resonance, by gradually moving the ultrasound beam and following the position of subsequent aortic segments and branches on the screen. Due to disturbances in ultrasound propagation caused by air-containing tissues, such as the trachea, bronchi and lungs as well as bones (sternum and ribs), each evaluation of the entire arch requires the use of a higher number of echocardiographic views. The presented data show that echocardiographic detection of the main details of aortic arch anomalies is possible in practically all cases. In the case of patients considered for surgical treatment, all unresolved issues should be clarified with CT angiography or MRI, enabling 3 dimensional reconstruction of vessels and other thoracic structures. Knowledge of the main elements of an abnormal arch is crucial for proper planning of this type of examination; therefore the diagnostic process should be always initiated with echocardiography. Echocardiography is often sufficient to answer all clinical questions and finalize the diagnostic process.

Non-invasive diagnosis of aortic arch anomalies in children - 15 years of own experience

Aim

To summarize our experience in echocardiographic diagnosis of aortic arch anomalies in pediatric patients.

Materials and methods

A retrospective assessment of echocardiographic findings in Echo-Lab patients of the Pediatric Cardiac Surgery Department, who were diagnosed with an anomalous aortic arch between 2003 and 2018.

Results

The diagnosis of an abnormal course of the aortic arch and/or its branches was established in 115 children aged between 4 days and 17 years. The following types of anomalies were detected: left aortic arch with aberrant right subclavian artery in 42 patients; right aortic arch with left brachiocephalic trunk in 14 patients; right aortic arch, aberrant left subclavian artery in 36 patients; double aortic arch in 14 patients; and other, more complex types in 9 patients. The main elements of defects were correctly identified by echo in all cases. We decided to additionally perform computed tomography angiography in 32 patients to clarify all details necessary to qualify patients for surgery and establish the surgical plan.

Conclusions

1. Echocardiography strictly following the pre-determined protocol has 100% sensitivity in the detection of basic elements of aortic arch anomaly and is a perfect tool for diagnostic process initiation. 2. Since it is not possible to visualize all anatomic details, the qualification for surgery should by based on computed tomography angiography or cardiac magnetic resonance imaging, which precisely visualize both abnormal vessels and compressed structures.

Patent ductus arteriosus coexisting with a left brachiocephalic artery originating from the descending aorta: A case report

RATIONAL

Patent ductus arteriosus (PDA) and a coexisting left brachiocephalic artery originating from the descending aorta is an extremely rare anomaly of unknown etiology.

PATIENT CONCERNS

Herein we report a 3-year-old female who was found to have this condition during intervention process to close PDA.

DIAGNOSIS

The patient was diagnosed with PDA coexisting with left brachiocephalic artery through angiography.

INTERVENTION

Intervention involved transcatheter closure of the pulmonary side of PDA with coils.

OUTCOMES

At 6-months follow up, the patient was well, with no symptoms and normal flow through the left carotid artery.

LESSONS

PDA coexisting with left brachiocephalic artery originating from the descending aorta is a very rare anomaly. When this variety of PDA is closed, it is important to avoid affecting the blood flow in the left brachiocephalic trunk. For this reason, closure on the side of the pulmonary artery may be the best solution.

Right aortic arch with bilateral arterial duct and nonconfluent pulmonary arteries without associated cardiac defects: Prenatal diagnosis and successful postnatal treatment

We describe a rare case of right aortic arch with bilateral arterial duct and disconnected left pulmonary artery. Prenatal diagnosis allowed to plan delivery at the referral center and to maintain perfusion of the disconnected pulmonary artery through prostaglandin E₁ infusion until surgical reconnection was performed. Early postnatal treatment avoided functional loss of the left lung that would have happened if malformation had not been identified before birth.

Congenital anomalies of the aortic arch

Congenital anomalies of the aortic arch include diverse subgroups of malformations that may be clinically silent or may present with severe respiratory or esophageal symptoms especially when associated with complete vascular rings. These anomalies may be isolated or may be associated with other congenital heart diseases. Volume rendered computed tomography (CT) and magnetic resonance angiography (MRA) help in preoperative surgical planning by providing information about the complex relationship of aortic arch and its branches to the trachea and esophagus. Three dimensional capabilities of both computed tomography angiography (CTA) and MRA are helpful in determining evidence of tracheal or esophageal compression or other high-risk features in patients with a complete vascular ring.

Characteristics of prenatally detected right aortic arch cases in a single institution

This study aimed to elucidate the diagnostic process, the associated anomalies and the perinatal outcomes of right aortic arch (RAA) in a group of low-risk patients. The obstetric imaging database and digital patient files were reviewed between January 2015 and June 2016. There were 12 RAA cases detected prenatally. Seven foetuses had an aberrant left subclavian artery and one foetus had mirror image branching. The prevalence of RAA was 1.8 in 1000. Invasive prenatal diagnosis was offered to patients and seven tests were performed. There was one associated cardiac anomaly (8.3%) and one extra-cardiac anomaly (8.3%) in the same foetus which cordocentesis revealed trisomy 21. There were also two 22q11.2 microdeletion cases with isolated RAA with aberrant left subclavian arteries. All patients have given live births except one patient has chosen a termination of pregnancy for 22q11.2 microdeletion. The median follow-up time of the newborns was 21 months. None of the babies required surgery for RAA during follow-up. All the babies are alive, except for the one with trisomy 21, who dead at 5 months due to the surgical complications of an oesophageal atresia operation. Patients with an RAA foetus should be offered for foetal karyotyping and analysis for 22q11.2 microdeletion. When isolated, RAA has usually a good prognosis and rarely requires cardiac surgery. Impact Statement What is already known on this subject? Prenatal diagnosis of RAA should prompt a detailed cardiac and extra-cardiac ultrasound examination. When isolated, RAA is associated with 22q11 deletion and aneuploidies in 4.6% and 5.1%, of cases respectively. What the results of this study add? Our study showed that 28.5% of isolated RAA cases are associated with 22q11.2 microdeletion. Cardiac surgery is rarely required when RAA is an isolated anomaly. What the implications are of these findings for clinical practice and/or further research? Invasive prenatal testing for karyotypes and 22q11.2 microdeletion should be offered to patients with RAA, even in the case of an isolated one. Further larger studies are needed to confirm this finding.

High incidence of progressive stenosis in aberrant left subclavian artery with right aortic arch

Right aortic arch with aberrant left subclavian artery (RAA/aLSCA) is a rare aortic arch anomaly. The clinical association of aLSCA stenosis with RAA/aLSCA has not yet been fully elucidated. The aim of this study was to investigate the diagnosis, incidence, management and outcome of aLSCA stenosis in infants with prenatally diagnosed RAA/aLSCA. Ten fetuses who were diagnosed as having RAA/aLSCA in Kyushu University Hospital between January 2011 and December 2014 were enrolled. The maternal and child medical records were reviewed to investigate sex, gestational age at the fetal diagnosis, gestational age and body weight at birth, the findings of computed tomography (CT), Doppler ultrasonography of the vertebral artery and angiography, and the complications and outcomes of aLSCA stenosis. In 8 of 10 patients, aLSCA stenosis was identified on the first CT examination after birth. No patients had dysphagia or respiratory distress. The stenosis spontaneously resolved in 3 patients. In 4 of the 5 remaining patients, aLSCA stenosis progressed, including one case in which complete occlusion occurred-the case was associated with retrograde flow from the left vertebral artery supplying the distal LSCA. Balloon angioplasty was successfully used to treat stenosis in two cases. The subclavian steal phenomenon and developmental problems were not observed in any patients. aLSCA stenosis was identified in 80% of patients with RAA/aLSCA after birth. The early detection and elective treatment of stenotic lesions may be required to prevent complete occlusion during the development of the cardiovascular and cerebrovascular systems.

Pathogenesis of solitary right aortic arch: a mass effect hypothesis based on observations of serial human embryonic sections

In general, solitary right aortic arch carries the left-sided ductus arteriosus communicating between the left subclavian and pulmonary arteries or the right-sided ductus connecting the descending aorta to the left pulmonary artery. Serial sections of fifteen 5- to 6-week-old embryos and ten 8- to 9-week-old fetuses suggested that the pathogenesis was unrelated to inversion due to dysfunction in gene cascades that control the systemic left/right axis. With inversion, conversely, the ductus or the sixth pharyngeal arch artery should connect to the right pulmonary artery. The disappearance of the right aortic arch started before the caudal migration of the aortic attachment of the ductus. Sympathetic nerve ganglia developed immediately posterior to both aortae, with a single embryonic specimen showing a large ganglion at the midline close to the union of the aortic arches. These ganglia may interfere with blood flow through the distal left arch, resulting in the ductus ending at the descending aorta behind the oesophagus. In another fetus examined, a midline shift of the ductus course resulted in the trachea curving posteriorly. Therefore, solitary right arch is likely to accompany abnormalities of the surrounding structures. The timing and site of the obstruction should be different between types: an almost midline obstruction near the aortic union needed for the development of the left-sided ductus and a distal obstruction near the left subclavian arterial origin needed for the development of the right-sided ductus. A mass effect of the sympathetic ganglia may explain the pathogenesis of any type of anomalous ductus arteriosus shown in previous reports of the solitary right arch.

Multidetector Computed Tomography for Congenital Anomalies of the Aortic Arch: Vascular Rings

The development of multidetector computed tomography has triggered a revolution in the study of the aorta and other large vessels and has replaced angiography in the diagnosis of congenital anomalies of the aortic arch, particularly vascular rings. The major advantage of multidetector computed tomography is that it permits clear 3-dimensional assessment of not only vascular structures, but also airway and esophageal compression. The current update aims to summarize the embryonic development of the aortic arch and the developmental anomalies leading to vascular ring formation and to discuss the current diagnostic and therapeutic role of multidetector computed tomography in this field.

Right Aortic Arch with Aplasia of the Left Brachiocephalic Trunk Presented as Systolic Blood Pressure Difference Between Upper Extremities

Background

The right aortic arch with mirror-image of branching arteries without coexisting congenital heart disease is a very rare anomaly.

Case Report

We report a case of the right-sided aortic arch with aplasia of the left brachiocephalic trunk in a 64-year-old women, presenting difference in systolic blood pressure between upper extremities. The history of the patient and angio-CT findings were described and visualized with images.

Conclusions

The knowledge of vascular variations is important for the clinical and therapeutic aspects.

Fetal Aortic Arch Anomalies: Key Sonographic Views for Their Differential Diagnosis and Clinical Implications Using the Cardiovascular System Sonographic Evaluation Protocol

Aortic arch anomalies are present in 1% to 2% of the general population and are commonly associated with congenital heart disease, chromosomal defects, and tracheaesophageal compression in postnatal life. The sonographically based detection of aortic arch anomalies lies in the 3-vessel and trachea view. Although highly sensitive, this view alone does not allow identification of the aortic arch branching pattern, which prevents an accurate diagnosis. The systematic addition of a subclavian artery view as part of a standardized procedure may be useful in the differential diagnosis of these conditions. We describe the sonographic assessment of fetal aortic arch anomalies by combining 2 fetal transverse views: the 3-vessel and trachea view and the subclavian artery view, which are included in the cardiovascular system sonographic evaluation protocol. We also review the sonographic findings and the clinical implications of fetal aortic arch anomalies.

Useful signs for the assessment of vascular rings on cross-sectional imaging

Vascular rings can be challenging to diagnose because they can contain atretic portions not detectable with current imaging modalities. In these cases, where the compressed airway and esophagus are not encircled by patent, opacified vessels, there are useful secondary signs that should be considered and should raise suspicion for the presence of a vascular ring. These signs include a double aortic arch, the four-vessel sign, the distorted subclavian artery sign, a diverticulum of Kommerell, a ductal diverticulum contralateral to the aortic arch, and a descending aorta contralateral to the arch or circumflex aorta. If none of these findings is present, a ring can be excluded with confidence.

Co-existence of patent ductus arteriosus and left brachiocephalic artery: a case report

Patent ductus arteriosus (PDA) may exist with other cardiovascular anomalies, which must be considered at the time of diagnosis. We report a rare co-existence of PDA and a variant of aortic arch branching pattern in a 12-year old Tanzanian female patient during surgery to close a PDA. In this case, the ‘left brachiocephalic trunk’ was seen to arise from the arch of aorta distal to the origin of the right brachiocephalic trunk. We discuss the relevant literature, its potential embryologic development and clinical significance.

Rings and slings revisited

Vascular rings and pulmonary artery slings are rare congenital anomalies that often present with symptoms of tracheal and esophageal compression. These can involve the aortic arch branches and pulmonary arteries, respectively. This review illustrates the current role of MR imaging, highlights its advantages, and provides insight into the diagnosis of these anomalies by describing the embryology and characteristic imaging features of these lesions.

Prenatal diagnosis and outcome of right aortic arch without significant intracardiac anomaly

BACKGROUND

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

METHODS

A retrospective study was completed of all fetuses diagnosed with RAA with normal or near normal intracardiac anatomy between 1999 and 2011. The aim was to evaluate the presence of RAA with complete ultrasonic 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 with the 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 or near normal intracardiac anatomy. Gestational age at diagnosis ranged from 19 to 34 weeks (mean, 23 weeks). Isolated RAAs were found in 50 fetuses, and double aortic arches (DAAs) were recognized in eight other cases. The postnatal cohort consisted of 44 newborns with RAAs and eight with DAAs (two were lost to follow-up, and four pregnancies were terminated). Postnatal echocardiography confirmed the prenatal diagnosis of RAA in 41 of 45 children, and four were found to have DAAs. Three of seven fetuses diagnosed prenatally as having DAAs were found to have only RAAs. Fourteen fetuses underwent karyotyping; two had 22q11 deletion and two 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 indicated in all symptomatic patients except one, whose symptoms resolved. One asymptomatic patient underwent operation for significant compression of the trachea.

CONCLUSIONS

RAA on fetal ultrasonography may indicate vascular and chromosomal abnormalities that may complicate postnatal management. When RAA is identified, fetal karyotype analysis (including the integrity of 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 prenatal ultrasound.

Variations in the Branching Pattern of the Aortic Arch Detected with Computerized Tomography Angiography

Objectives. The aim was to determine the prevalence of aortic arch variations in 881 patients who underwent neck CT angiography for various reasons. Material and Methods. 881 patients were included in the study who had undergone neck CT angiography between 2010 and 2013. Results. Of 881 patients, 770 (87.4%) patients with classic branching pattern of the aortic arch (AA) were observed. Variations in branching pattern were seen in 111 (12.6%) patients. The most common variation was the origination of the left common carotid artery (LCCA) from the brachiocephalic trunk (BCT). This pattern was observed in 64 (7.2%) cases. In 25 (2.8%) cases, the left vertebral artery (LVA) originated directly from the AA between the origin of the LCCA and left subclavian artery (SCA). 17 (1.9%) cases had aberrant right subclavian artery. Three (0.3%) cases showed right aortic arch. Two cases had right aortic arch with aberrant left subclavian artery. Conclusions. Variations in the branching pattern of the AA are not rare. Head and neck surgeons and interventional radiologists should be aware of aortic arch variations. CTA is a reliable imaging method for demonstrating anatomical features and variations of the AA.

Common Cervical and Cerebral Vascular Variants

Successful open and endovascular carotid artery intervention depends on a thorough foundational knowledge of cervical and intracranial vascular anatomy. It is essential for the carotid interventionist to be familiar with the common and rare variants of the cervical and intracranial vasculature, and to understand the implications of these variants for the performance of carotid intervention with protection of the distal circulation. This article provides interventionists with a basic description of the normal and relevant variant vascular anatomy from the aortic arch to the circle of Willis, and outlines the potential difficulties that specific variants may present for endovascular therapy.

Right aortic arch diagnosed antenatally: associations and outcome in 98 fetuses

OBJECTIVE

To analyse the main characteristics, associated conditions and outcome of right aortic arch (RAA) detected in fetal life, and to assess if further investigation is required in cases of isolated RAA.

METHODS

Retrospective observational study of all fetuses diagnosed with a RAA between 2004 and 2012 at a tertiary centre for fetal cardiology.

RESULTS

A RAA was identified in 98 fetuses: 27 had normal intracardiac anatomy and 71 were associated with other congenital heart disease (CHD); conotruncal anomalies being the most common. An aberrant left subclavian artery was diagnosed in 18.4% of cases, a double aortic arch in 6.1%, and 12.2% had a vascular ring confirmed after birth. Overall, an extracardiac anomaly was present in 31.6% of the patients and a chromosomal anomaly in 15.3%, with half of the latter cases being 22q11.2 microdeletion. Extracardiac and chromosomal anomalies were more commonly associated with RAA with structural CHD (39.4% and 19.7%, respectively), compared to cases of RAA with normal intracardiac anatomy (11.1% and 3.7%, respectively) (p<0.05). First year mortality was 10.3%, with all deaths being in cases with associated structural CHD.

CONCLUSIONS

Detailed fetal extracardiac examination should be undertaken in all cases of RAA. Isolated RAA has a good prognosis, and in the majority of the patients it is an asymptomatic vascular variant with a relatively low risk for chromosomal anomaly. The prognosis of RAA with CHD depends on the complexity of the CHD and/or the associated extracardiac anomalies. In these cases, there is a higher risk for chromosomal anomaly, particularly 22q11.2 microdeletion.

Right ductus arteriosus: facts and theory

OBJECTIVE

To report fetal right-sided persistent ductus arteriosus (RPDA) in association with right aortic arch (RAA).

STUDY DESIGN

Extensive sonographic fetal anatomical scans were consecutively performed on 19,874 private, self-referred pregnant women who wanted early sonographic detection of fetal anomalies.

RESULTS

Of 19,874 transvaginal (TVS) sonographic examinations 40 fetuses had right aortic arch (RAA) and four of them (10%) had RPDA. We also diagnosed seven cases of RPDA with involvement of the left aortic arch where a right-curving pattern ("L" shape) parallel to the right pulmonary artery was suggestive of Rt. DA with left aortic arch. Only one (9%) of the RPDA cases was associated with a cardiac anomaly (double outlet right ventricle). None of the other eight RPDA cases had any discernible anomalies, and all of the fetuses with RPDA had normal karyotypes.

CONCLUSIONS

In 10% of the fetuses with right aortic arch the ductal arch was also on the right side. An unusual-looking DA may be a RPDA associated with the left aortic arch. In most cases, the RPDA is a normal variant not associated with other anomalies.

Aortic development and anomalies

Development of the aorta takes place during the third week of gestation. It is a complex process that can lead to a variety of congenital variants and pathological anomalies. In diagnostic and interventional radiology, knowledge of aortic abnormalities and variant branching sequence is crucially important. This article gives a systematic overview of anatomical variability of the aorta.

Diagnostic role of magnetic resonance imaging in identifying aortic arch anomalies

PURPOSE

The aim of this article was to assess the role of MRI in the diagnosis and management of a variety of complex aortic arch anomalies.

MATERIALS AND METHODS

Imaging was performed on a 1.5T Philips Gyroscan Intera. We retrospectively reviewed all cardiac MR scans performed from November 2003 to February 2007 at our institute to identify aortic arch anomalies. Magnetic resonance imaging included three-dimensional (3D) sagittal volume images, cine images, short axis ventricular volumes, phase contrast flow of great vessels, and 3D gadolinium magnetic resonance angiogram.

RESULTS

Three major categories of anomalies were identified in 47 patients: double aortic arch (n = 9), right-sided aortic arch with mirror image branching (n = 28), and aberrant right subclavian artery (n = 10). In the double aortic arch group, six patients were symptomatic, and four of them underwent a surgical division. Magnetic resonance imaging was used to plan the surgical management. In the other two groups, no patient presented with symptoms of airway or esophageal compression, and the arch abnormalities were noticed during investigation for other associated cardiac disease. However, we noticed a strong correlation with well-defined subgroups of congenital heart disease. Right-sided aortic arch was seen in patients with pulmonary atresia with ventricular septal defect (46.4%), tetralogy of Fallot (32.1%), and double outlet right ventricle with right atrial isomerism (14.2%). Seventy percent of the patients with aberrant right subclavian artery had aortic coarctation, and another case presented a complete aortic arch interruption.

CONCLUSION

Magnetic resonance imaging is an important diagnostic tool in identifying anomalies of the aortic arch and its branches and can be considered the imaging technique of choice when planning surgical management, especially when there are associated cardiac anomalies.

The role of magnetic resonance imaging in the assessment of suspected extrinsic tracheobronchial compression due to vascular anomalies

AIMS

To evaluate the role of magnetic resonance imaging (MRI) in the assessment of children with suspected extrinsic tracheobronchial compression due to vascular anomalies.

METHODS

Retrospective case note review in a tertiary referral centre. Twenty nine children who underwent dynamic laryngotracheobronchoscopy (DLTB) and were found to have a clinical suspicion of extrinsic tracheobronchial compression were evaluated. All subsequently underwent thoracic MRI within 10 days. The findings on endoscopy were compared to those of MRI, and where performed, echocardiography, aortography, and surgery.

RESULTS

There were 17 males and 12 females (mean age 5 months, range 28 weeks gestation to 60 months). The most common presenting features were stridor and cyanotic episodes. MRI showed abnormalities in 21 patients. There were five vascular rings (three double aortic arches and two right aortic arches) and 11 cases of innominate artery compression. Other vascular anomalies noted included aberrant right subclavian artery and aneurysmal left pulmonary artery. Echocardiography was generally found to be unhelpful in the diagnosis of extra-cardiac vascular abnormalities. Angiography was subsequently conducted in eight children; findings agreed with those shown on MRI. Surgery was performed on all five vascular rings, one innominate artery compression, and one aneurysmal left pulmonary artery. Surgical findings were also compatible with the preoperative MRI.

CONCLUSIONS

This study shows the successful use of MRI as the initial imaging modality in endoscopically suspected extrinsic vascular compression of the upper airway. It enables accurate delineation of vascular anomalies and, unlike aortography, is non-invasive and does not require the use of contrast media.

Perinatal management of right aortic arch with aberrant left subclavian artery associated with critical stenosis of the subclavian artery in a newborn

A right-sided aortic arch with an aberrant left subclavian artery is a congenital vascular anomaly that is easily detectable in utero at the level of the three vessels and trachea view, but which is rarely symptomatic in the neonate. We present a newborn with prenatally diagnosed right-sided aortic arch and aberrant subclavian artery who showed a clinically relevant stenosis of the subclavian artery during the first week of life. An intravascular stent was implanted into the stenosis of the aberrant left subclavian artery by catheterization. This case report demonstrates that a right-sided aortic arch with an aberrant subclavian artery can be diagnosed prenatally, that in these patients a stenosis of the subclavian artery can occur in early infancy and requires awareness of the neonatologist or pediatrician, and that stent implantation represents a minimally invasive therapeutic approach.

Right-sided aortic arch and tetralogy of Fallot in humans--a morphological study of 10 cases

INTRODUCTION

A right-sided aortic arch (RAA) represents a rare anomaly of the cardiovascular system. In situs solitus, RAA is typically associated with malformations of the cardiac outflow tract such as tetralogy of Fallot (TOF). RAA is classified according to the course and ramification pattern and the position of the arterial duct. Varying data on the frequency of the RAA ramification patterns are reported in the literature.

METHODS

We examined 10 formalin-fixed human specimens aged 3 weeks to 10 years. In each case, we investigated the course of the aortic arch, its ramification and the position and course of the arterial duct/ligament as well as associated cardiac malformations.

RESULTS

Three different ramification patterns became evident: mirror-image branching (n=7), aberrant left subclavian artery (n=2) and isolated left subclavian artery (n=1). The arterial duct was situated either on the left side connecting the left pulmonary artery to the left subclavian artery (n=6) or on the right-hand side between the right pulmonary artery and the aortic arch (n=3). The duct was absent in one case. The most frequent combination was a mirror-image branching pattern with a left-sided arterial duct (n=4).

CONCLUSIONS

The various ramification patterns of the RAA are explained by differences in growth and involution of the embryonic double-aortic arch "anlage." Genetic factors as well as mechanical influences may be involved in the aetiology of RAA. The percentage of the various RAA patterns strongly depends on the examination material available.