Prenatal diagnosis of right aortic arch and aberrant left subclavian artery in association with bilateral ductus arteriosus by two-and four-dimensional echocardiography: a case of rare vascular ring and review of literature

The purpose of our study was to describe patterns of airway compression identified on cross-sectional imaging in infants and children with either right aortic arch and aberrant left subclavian artery or left aortic arch with aberrant right subclavian artery. Data from MR imaging and CT performed to evaluate pediatric patients for extrinsic airway compression were reviewed for cases that revealed an aberrant right or left subclavian artery. Clinical, endoscopic, and imaging findings in identified cases were reviewed. Recurrent patterns of extrinsic compression were reviewed among cases. Twelve patients with right aortic arch with aberrant left subclavian artery and nine patients with left aortic arch and aberrant right subclavian artery were identified. All 12 with right aortic arch with aberrant left subclavian artery had airway compression shown, with multiple sites or diffuse compression in six. Of these 12 patients, nine had compression at the level of the arch and aberrant subclavian artery (10 had Kommerell's diverticulum), and nine had compression of the distal airway in association with a midline descending aorta. Five of the nine patients with left aortic arch and aberrant right subclavian artery had airway compression shown, all at the level of the arch and aberrant subclavian artery. None of these compressions was associated with either Kommerell's diverticulum or midline descending aorta. Both right and left aberrant subclavian arteries can be associated with symptomatic airway compression, but the patterns of compression are different. The airway compression in right aortic arch with aberrant left subclavian artery is often associated with either Kommerell's diverticulum or midline descending aorta, whereas compression associated with left aortic arch and aberrant right subclavian artery is not.

NOT ALL THAT WHEEZES IS ASTHMA: A CASE OF KOMMERELL DIVERTICULUM

Objective To explore the diagnosis and surgical treatment of patients with right aortic arch and left artery ligament. Methods The clinical data of 64 patients with right aortic arch left arterial ligament were analyzed retrospectively from January 1, 2008 to April 1, 2017. There were 43 boys and 21 girls with an average age of (9.87±11.12) months and an average body weight of (6.52±4.07) kg. Among 39 cases of right aortic arch and aberrant left subclavian artery, significant Kommerell diverticulum was concurrent in 12 cases, including mirror branch type A (n=23) and mirror branch B type (n=2). Except for mirror branch of children with type B without obvious respiratory and gastrointestinal symptoms, all children were operated. The cases of aberrant left subclavian artery and mirror branch A underwent simple arterial ligament dislocation plus significant Kommerell diverticulum under left subclavian artery transplantation, correction of of vagal left subclavian artery malformations and diverticulotomy. Results All children were successfully operated. Wheezing and gastrointestinal symptoms became significantly relieved. There was no chylothorax, diaphragmatic or paralytic nerve injury. The average ventilator support duration was (24.18±21.32)(2-48) h. The average stay duration of intensive care unit (ICU) was (53.24±20.57)(24-72) hours and it was not significantly different from that of other children during the same period. Discharge occurred after 7-10 days. For 42 cases, the follow-up period was 3 to 7 months. All wheezing symptoms gradually disappeared. Enhanced computed tomography (CT) revealed no abnormality of subclavian artery, aortic arch or bilateral upper extremity arteries. Conclusions Right aortic arch and left artery ligament should be operated promptly after a definite diagnosis through enhanced cardiac CT and fiberoptic bronchoscopy. Surgery is indicated for relieving tracheal compression symptoms in children. Timely release of compressing vascular ring on trachea and esophagus is vital for improving the prognosis. Key words: Aortic arch; Subclavian artery; Tracheal stenosis

Repair of Kommerell's Diverticulum and Aberrant Subclavian Arteries: Classification of the Five Groups in Declining Frequency and Their Operative Approaches

A nine-year-old female was referred for the evaluation of murmur. She had a history of frequent lower respiratory tract infections. There were no complaints of esophagus compression such as resistant vomiting or dysphagia. There was no finding of compression in esophagus. Transthoracic echocardiography revealed a right aortic arch, a small restrictive inlet ventricular septal defect and crossed pulmonary arteries. Transthoracic echocardiography failed to visualize the branches of aortic arch. She underwent computerized tomography (CT) and it determined a right aortic arch. The left common carotid artery was the first main artery to arise from the arch, is followed by the right common carotid artery, right subclavian and left subclavian arteries. The aberrant left subclavian artery was originated from a Kommerell’s diverticulum at the distal part of aortic arch which compressed the esophagus (Figure 1). CT also showed the crossed pulmonary arteries (Figure 1). Right aortic arch and aberrant left subclavian artery that originates from Kommerell’s diverticulum is a rare condition that is diagnosed in approximately %0.1 of the population (1). However, this condition is mostly asymptomatic in general, some patients may present with the compression symptoms to the esophagus and trachea. Children who present with airway symptoms such as a combination of stridor, apnea, cyanosis, or recurrent infection. (2,3). Crossed pulmonary arteries (CPAs) is an abnormality in which the ostium of the left pulmonary artery originates superior to the right pulmonary artery and to its right. It is generally accompanied by other congenital heart defects, extra cardiac anomalies, and certain genetic problems. To date, only a few cases have been reported, and most of these cases have been associated with complex cardiac abnormalities and genetic syndromes (4). This is the first case of right aortic arch associated with aberrant left subclavian artery and crossed pulmonary arteries from Turkey.

Objective To investigate the ultrasonic imaging features of and differential diagnosis methods for the right aortic arch, to analyze the causes of missed diagnosis and misdiagnosis, and to further improve the accuracy of prenatal ultrasound diagnosis. Methods Cardiac screening examination of the fetus was carried out with views of gray-scale and color Doppler or power Doppler imaging (PDI). When the three-vessel tracheal (3VT) view found that the aortic arch was located in the right of the trachea, the coronary views of the trachea and its branches were obtained to further clarify the relationship among the aortic arch, arterial ductus, and trachea. The sonographic features of 31 cases of fetal right aortic arch were summarized, and the reasons for misdiagnosis were analyzed. Results Of the 31 cases of fetal right aortic arch diagnosed by prenatal ultrasound, 20 were alive, 15 were induced, and 6 were lost. As for the results of echocardiography for postpartum children, operation or autopsy were obtained in 31 cases, of which 6 had misdiagnosis or missed diagnosis by prenatal ultrasonography. The coronal views of the trachea and its branches were not obtained in two cases of fetal left aortic arch, and they were misdiagnosed as right aortic arch because the transversely sectioned bronchus were mistaken as the transversely sectioned trachea in the 3VT view. In two cases of right aortic arch with aberrant left subclavian artery, the left common carotid artery was misdiagnosed as a stunted left arch, which resulted in a misdiagnosis as a double aortic arch of the advantage type. In two cases of right aortic arch combined with cardiac defects, right aortic arch was missed in prenatal ultrasound diagnosis. Of 20 children who were followed, 13 were diagnosed with isolated right aortic arch, 2 with combined persistent left superior cavity, 1 with combined 2-3 lumbar vertebral body fusion, and 2 with combined right aortic arch inner or outer non-complex structure abnormality. Follow-up was conducted to the maximum age up to 3 years and 6 months, and 18 of these cases were in good condition and showed no symptoms of respiratory tract compression. One case suffered from complicated intracardiac malformation combined with IDD type congenitally corrected transposition of the great arteries. The child is currently in good condition 11 months after the delivery. One case suffered from combined esophageal atresia and died 14 days after delivery. Chromosome karyotype determination was performed in 6 cases, of whom 5 were normal and 1 was confirmed to have 18-trisomy with severe intracardiac multiple malformation. Conclusions The 3VT view is the most important view for diagnosis of right aortic arch of fetus. The accuracy of prenatal ultrasound diagnosis can be improved through the combination of the 3VT view and the coronal view of the trachea and its branches. Simple right aortic arch offers a good prognosis, and the prognosis of right aortic arch with severe ectopic and extracardial malformations depends on the severity of the combined malformation. Key words: Fetal right aortic arch; Ultrasonography, prenatal; Pregnancy outcome

Objective To explore the value of MRI in the diagnosis of fetal aortic arch anomalies. Methods We retrospectively collected 10 fetuses with aortic arch anomalies indicated by prenatal ultrasound and underwent MR examination and were subsequently proven by autopsy or post-birth follow-up from 320 pregnant women. We focused on the observations of the location of the aortic arch and brachiocephalic artery anomalies, the locations of the liver and stomach in the abdominal cavity, and the large vessels in abdomen. The above-mentioned finding were compared with prenatal ultrasound and follow-up findings. Results Of 10 cases, right aortic arch with aberrant left subclavian artery was seen in 7 cases, right aortic arch with the mirror branch, left aortic arch with aberrant right subclavian artery, right aortic arch with aberrant left subclavian artery combined with cervical aortic arch and double aortic arch was seen in 1 case, respectively. All aortic arch anomalies detected by MRI were consistent with post-birth or autopsy findings. Ultrasound misdiagnosed aortic branch malformation in 5 places, which included right aortic arch but misdiagnosed aberrant left subclavian artery in 2 cases, right aortic arch never diagnosed mirror branch anomaly in 1 case, right aortic arch with left subclavian artery misdiagnosed cervical aortic arch in 1 case, left atrial isomerism but misdiagnosed left aortic arch with aberrant right subclavian artery in 1 case; One double aortic arch was misdiagnosed as right aortic arch with aberrant left subclavian artery in ultrasound. Conclusion Fetal cardiovascular MRI is an effective and supplementary examination to complement ultrasound in diagnosis of fetal aortic arch anomalies. Key words: Fetus; Aorta,thoracic; Vascular malformations; Magnetic resonance imaging

Objective To investigate the value of prenatal echocardiographic diagnosis of anomalies of the right aortic arch(RAA) and its branch type, and provide rapid diagnostic methods. Methods A retrospective analysis of 55 cases of RAA of prenatal ultrasound diagnosis results, and their imaging characteristics were summarized. Results There were 55 cases of anomalies of the RAA, included 42 cases of RAA with aberrant left subclavian artery(RAA-ALSA) and 13 cases of RAA with mirror image branching pattern(RAA-MB), 1 case of double aortic arch(DAA) was misdiagnosed as RAA. The prenatal echocardiographic characteristics of RAA-ALSA: in three-vessel-aortic arch view, the first branch of the aortic arch was the left carotid artery, which ran in front of the trachea, and ALSA ran behind the trachea and esophagus. The prenatal echocardiographic characteristics of RAA-MB: the first branch of the aortic arch was the brachiocephalic trunk, which ran in front of the trachea and was divided to the left carotid artery and the left subclavian artery. Conclusions Prenatal ultrasound can qunickly and accurately diagnose anomalies of the right aortic arch and its branch type according to the direction, thickness and secondary branches of the first branch of the aortic arch. The location of arterial duct is helpful to judge the formation of vascular ring. Key words: Ultrasonography, prenatal; Right aortic arch; Vascular ring

Vascular rings are congenital aortic arch anomalies that compress the trachea and esophagus, causing symptoms related to these two structures. One of the common types of vascular ring is formed by a right aortic arch, aberrant left subclavian artery and left-sided ductus arteriosus1. Bilateral ductus arteriosus is uncommon and can also result in a vascular ring2; it has been reported previously in association with right aortic arch and aberrant left subclavian artery3–5. We describe a rare vascular ring composed of a right aortic arch, aberrant left subclavian artery and bilateral ductus arteriosus. A 27-year-old woman was referred to our institution at 25 weeks of gestation for fetal echocardiography because of a suspected vascular ring. Two-dimensional color Doppler imaging revealed a right aortic arch, aberrant left subclavian artery and bilateral ductus arteriosus, resulting in two vascular rings, one being small and O-shaped and the other being U-shaped (Figure 1). Four-dimensional (4D) color Doppler with spatiotemporal image correlation (STIC) HD-flow mode (Voluson E10; GE Healthcare, Zipf, Austria) clearly showed the spatial relationships of these vessels and the trachea (Figure 1). No extracardiac or other cardiac anomalies were found. Fetal karyotyping and chromosomal microarray analysis (Affymetrix 750K; Thermo Fisher Scientific, Santa Clara, CA, USA) were normal. A female neonate was delivered vaginally at 40 + 5 weeks of gestation with a birth weight of 3280 g. Computed tomography (CT) was performed 3 days postpartum, which confirmed the formation of a complete vascular ring by the right aortic arch, aberrant left subclavian artery and bilateral ductus arteriosus. A slight indentation on the left side of the trachea was noted, which was produced by the left posterior ductus arteriosus (Figure 2). During the 2-month follow-up period, the left and right ductus arteriosus were observed to close spontaneously at 5 and 42 days after delivery, respectively. The patient had remained asymptomatic at the time of writing. Prenatal detection of a vascular ring by fetal echocardiography in this case had the following clinical implications: first, fetal karyotype analysis and genetic testing were recommended4; second, close monitoring of the patency of bilateral ductus arteriosus after birth was indicated as a precautionary measure against excessive pulmonary blood flow. The O-shaped complete ring appears to be anatomically ‘tighter’ than the U-shaped ring formed by a right aortic arch, aberrant left subclavian artery and left-sided ductus arteriosus. Surgical release of the vascular ring is likely required. Thus, further CT imaging and long-term follow-up are warranted. In conclusion, we present a case of a rare vascular ring formed by a right aortic arch and aberrant left subclavian artery in association with bilateral ductus arteriosus. Prenatal diagnosis is important to facilitate early clinical and imaging evaluation. Fetal echocardiography with application of 4D color Doppler with STIC HD-flow mode facilitates demonstration of the spatial relationships of the aortic arch branches and trachea. CT imaging after birth provides accurate anatomical information regarding the severity of the narrowing of the ring as well as the tracheoesophageal compression. This work was funded by the National Key Research and Development Program (2016YFC1000500).

The authors report a case of a neonate that was operated on with the diagnosis of right aortic arch and aberrant left subclavian artery and anomalous origin of right pulmonary artery from ascending aorta. Computed tomography (CT) scan suggested double aortic arch and cardiac catheterization suggested anomalous origin of right pulmonary artery from ascending aorta versus aorto-pulmonary window. The final diagnosis was made at the operation. There was a right aortic arch and aberrant left subclavian artery and persistent ductus arteriosus. Surgical repair consisted of section of the ductus arteriosus and reimplantation of the right pulmonary artery in the main pulmonary artery.

Aortic arch anomalies refer to congenital malformations of position or branching pattern of the aortic arch. To-date, only a few small studies have documented prenatal detection of aortic arch anomalies. In this article, we share our experience in detecting aortic arch anomalies. Foetal echocardiograms, clinic and genetic histories of 33 patients who had been diagnosed with aortic arch anomaly from 2007 to 2015 were reviewed. In 15 patients, right aortic arch with mirror image branching; in 13 patients, right aortic arch with left ductus arteriosus and aberrant left subclavian artery; in three patients, left aortic arch with aberrant right subclavian artery; in one patient bilateral ductus and right aortic arch with aberrant left subclavian artery and in one patient double aortic arch were detected. In a patient with isolated right aortic arch, 22q11 microdeletion had been revealed. Given this data, we strongly suggest foetal karyotype analysis when aortic arch anomalies are identified.Impact StatementWhat is already known on this subject: The data about the prenatal diagnosis of aortic arch anomalies are limited.What the results of this study add: In our study, 653 patients were examined by foetal echocardiography during the study period. Thirty three patients who had been diagnosed with aortic arch anomaly prenatally and confirmed after delivery were enrolled in the study. In 15 patients, right aortic arch with mirror image branching; in 13 patients, right aortic arch with left ductus arteriosus and aberrant left subclavian artery; in three patients, left aortic arch with aberrant right subclavian artery; in one patient bilateral ductus and right aortic arch with aberrant left subclavian artery and in one patient double aortic arch were detected. Trisomy 18 was detected in the patient with bilateral ductus arteriosus and Di George syndrome (22q11 microdeletion) was determined in two patients with right aortic arch. While in the first patient, there were no other intracardiac anomalies; in the second patient with 22q11 microdeletion, Fallot tetralogy accompanied the right aortic arch.What the implications are of these findings for clinical practice and/or further research: This results showed that aortic arch anomalies can be associated with genetic anomalies even when they are found without other congenital heart disease. Given these data, we strongly suggest foetal karyotype analysis and genetic testing when aortic arch anomalies are identified.

A2.8-kg newborn girl was referred to our hospital for tetralogy of Fallot with a right aortic arch. ECG failed to provide a clear anatomic definition of the pulmonary blood supply. Cardiac catheterization disclosed a right aortic arch giving rise to 4 separate branches in the following sequence: right common carotid artery, right vertebral artery, right subclavian artery, and aberrant left subclavian artery (Figure 1). An isolated left common carotid artery, draining into the left pulmonary artery, was visualized by retrograde filling after selective injection into the right common carotid artery (Figure 2). Such a rare anomaly creates a left-to-right shunt at the arterial level, which becomes more significant when the pulmonary artery pressure lowers because of spontaneous or surgical right ductal closure. Isolation of the common carotid artery occurs only when the homolateral subclavian artery is aberrant so that the innominate artery cannot be formed. A bilateral patent ductus arteriosus connected the aortic isthmus to the right pulmonary artery and the isolated vessel to the left pulmonary artery. The main pulmonary artery and its branches were confirmed to be moderately and diffusely hypoplastic. Anomalous origin of the left anterior descending coronary artery from the right coronary artery was visualized. Via median sternotomy (Figure 3), the baby underwent aortic arch implantation of the isolated left carotid artery and 3-mm polytetrafluoroethylene systemic-to-pulmonary shunt interposition between the ascending aorta and the left pulmonary artery (Figure 4). Complete repair was deferred because of the coronary anomaly and the small size of the pulmonary arteries. The thymic gland was absent, thus supporting the clinical findings typical of DiGeorge syndrome. The patient survived the operation and is currently awaiting complete repair.

Type B Aortic Dissection Involving an Isolated Right-Sided Aortic Arch

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. 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. 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. 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.

Early Resection of Kommerell Diverticulum and Revascularization in Children With Right Aortic Arch and Aberrant Left Subclavian Artery.