Outcomes for Children With Vascular Ring Repair Using a Simple Surgical Approach.

INTRODUCTION: Vascular Rings (VRs) are congenital malformations of the aortic arch that can compress the trachea and esophagus producing symptoms. Approximately, 5%-10% of patients experience persistent symptoms postrepair and 9% require reintervention. There are various approaches to repair-simple ligation and division of the ring or more complex procedures. Our objective was to describe outcomes for VR repair using a "simple" surgical approach. METHODS: We identified patients who underwent VR repair from 2012 to 2022 at our institution. Clinical and surgical data, demographics, intraoperative, and postoperative outcomes were extracted from their electronic medical records. Outcomes were analyzed and regression analysis was used to identify risk factors for residual symptoms after repair. RESULTS: Ninety three patients with VR repair were included. Prevalence of symptoms were reduced following surgery (80% preoperative versus 13% postoperative, P 0.03). Tracheomalacia also decreased from 16% to 7% postrepair. No deaths were reported in our cohort and 2% of our patients required reintervention. Multivariable regression analysis showed that preoperative tracheomalacia was associated with having persistent symptoms after VR repair (odds ratio 6.2, 95% CI 1.02-37.6). CONCLUSIONS: Our institutional experience using a simple surgical approach showed a significant decrease in symptoms, a very low reintervention rate and no mortality. Preoperative tracheomalacia can be a risk factor for persistent symptoms postrepair. We believe a simple surgical approach for children with complete VR repair can be effective in relieving symptoms.

Double aortic arch: a comparison of fetal cardiovascular magnetic resonance, postnatal computed tomography and surgical findings.

BACKGROUND: In double aortic arch (DAA), one of the arches can demonstrate atretic portions postnatally, leading to diagnostic uncertainty due to overlap with isolated right aortic arch (RAA) variants. The main objective of this study is to demonstrate the morphological evolution of different DAA phenotypes from prenatal to postnatal life using three-dimensional (3D) fetal cardiac magnetic resonance (CMR) imaging and postnatal computed tomography (CT)/CMR imaging. METHODS: Three-dimensional fetal CMR was undertaken in fetuses with suspected DAA over a 6-year period (January 2016-January 2022). All cases with surgical confirmation of DAA were retrospectively studied and morphology on fetal CMR was compared to postnatal CT/CMR and surgical findings. RESULTS: Thirty-four fetuses with surgically confirmed DAA underwent fetal CMR. The RAA was dominant in 32/34 (94%). Postnatal CT/CMR was undertaken at a median age of 3.3 months (interquartile range 2.0-3.9) demonstrating DAA with patency of both arches in 10/34 (29%), with 7 showing signs of coarctation of the left aortic arch (LAA). The LAA isthmus was not present on CT/CMR in 22/34 (65%), and the transverse arch between left carotid and left subclavian artery was not present in 2 cases. CONCLUSION: Fetal CMR provides novel insights into perinatal evolution of DAA. The smaller LAA can develop coarctation or atresia related to postnatal constriction of the arterial duct, making diagnosis of DAA challenging with contrast-enhanced CT/CMR. This highlights the potentially important role for prenatal 3D vascular imaging and might improve the interpretation of postnatal imaging.

Management of esophageal cancer in patients with a right aortic arch or double aortic arch: a case series of 34 cases.

BACKGROUND: Few cases describing patients with a right aortic arch (RAA) or double aortic arch (DAA) and esophageal cancer (EC) have been reported. METHODS: We analyzed RAA and DAA cases treated with esophagectomy in our center's database and reported in English-language studies until April 1, 2023. Our study assessed the malformation characteristics and surgical details of EC patients with RAA and DAA. RESULTS: We extracted data of 24 EC patients with RAAs and 10 EC patients with DAAs. In both groups, the patients were more likely to be Japanese and male, to have squamous cell carcinoma and to have tumors located in the upper thoracic esophagus or middle thoracic esophagus. Left thoracotomy was commonly applied for RAA patients. For DAA patients, the proportions of left-sided and right-sided approaches were similar. Esophagectomy under video-assisted thoracoscopic surgery (VATS) in RAA or DAA patients had been performed on a routine basis in recent years. There were two anastomotic leakages in each group. Specifically, Kommerell diverticulum rupture occurred in 1 RAA patient; gastric tube dilation occurred in 1 DAA patient; and recurrent laryngeal nerve (RLN) injury occurred in 2 RAA patients. The postoperative course was uneventful for most patients in both cohorts. CONCLUSIONS: Esophageal carcinoma is rarely seen in patients with an RAA or DAA. To adequately dissect superior mediastinal LNs, an auxiliary incision (such as sternotomy), the left door open method or a preceding cervical procedure should be used appropriately. Esophagectomy, whether via thoracotomy or thoracoscopic surgery, can be performed safely for both RAA and DAA.

Relationship Between Quantitative Tracheal Geometry and Clinical Course in Various Types of Vascular Ring.

To investigate the relationship between quantitative tracheal geometry and clinical course among various types of vascular ring and to identify factors correlating with symptom presentation. Patients with vascular ring diagnosed between April 2010 and December 2022 were included. All the patients were classified as type 1 (complete double aortic arch); type 2 (incomplete double aortic arch); type 3 (circumflex aorta); type 4 (right aortic arch and aberrant left subclavian artery with a left retroesophageal diverticulum of Kommerell); or type 5 (mirror-imaged right aortic arch with retroesophageal aortic diverticulum). Their clinical characteristics and quantitative variables on computed tomography (CT) were compared. Of the 50 patients enrolled, those with type 1 tended to have a smaller luminal tracheal diameter at the level of the ring. The median symptom-free survival time was shortest in this group (16.0 days [95% confidence interval (CI): 9.4-51.0]), followed by type 3 (138.0 days [95% CI: 0.0-851.4]). Type 1 (hazard ratio [HR]: 9.0; 95% CI: 2.3-35.0; P = 0.001), type 3 (HR: 4.2; 95% CI: 1.4-13.2; P = 0.013), and the percentage of tracheal narrowing in the anteroposterior projection (HR: 0.87; 95% CI: 0.78-0.96; P = 0.008) were significantly associated with symptom presentation in the time-dependent course. The aortic arch encircling the entire circumference in type 1 and high-pressure vasculature in front of the vertebral body in types 1 and 3 may contribute to raising the risk of symptom presentation.

Narrowing Down the Symptomatology of Isolated Vascular Rings in Children.

Vascular rings may cause respiratory or gastrointestinal symptoms due to compression of the trachea and/or esophagus. Advances in imaging have enabled early detection in asymptomatic patients posing new management dilemmas. Surgery is expected to relieve symptoms, although this has not been well studied. We sought to evaluate the presence and pattern of symptoms associated with vascular rings before surgical intervention and to detail symptom resolution after surgery. A 10-year retrospective review of patients diagnosed with an isolated vascular ring was performed between January 2010 and December 2019. 100 patients were identified; 35 double aortic arch (DAA) and 65 right aortic arch and left ligamentum arteriosum (RALL). 73 patients were symptomatic on presentation; 47 had respiratory, 5 had gastrointestinal, and 21 had both types of symptoms. Surgical repair was performed in 75 patients; 74 were symptomatic. Respiratory symptoms were more likely in patients with preoperative tracheal narrowing (p < 0.001). Moderate-severe respiratory symptoms led to surgery in RALL patients (OR 10.6, p = 0.0001). DAA patients were more likely to undergo surgery (p < 0.001) irrespective of symptom severity. At a median post-surgical follow-up of 4 months, there was a significant reduction in symptom burden (p < 0.001), except for asthma symptoms (p = 0.131). Symptom resolution was not dependent on the vascular ring anatomy (p = 0.331) or the age at operation (p = 0.158). Vascular rings are typically accompanied by respiratory symptoms and less commonly GI symptoms, both of which resolve in most patients after surgery. Those who present predominantly with asthma-like symptoms may not achieve resolution after surgery.

Variations in the Evaluation and Management of Vascular Rings: A Survey of American Clinicians.

Vascular rings are arterial malformations that lead to the compression of the trachea and/or esophagus. While "tight" rings often produce symptoms and require surgery, "loose" rings rarely produce symptoms. Given advances in fetal echocardiography, this diagnosis is now more often made prenatally. This poses a new conundrum in the management of asymptomatic patients, leading to practice variation and creating a target for clinical system improvement. Hence, we conducted this survey aiming to demonstrate the practice variation existing in current evaluation and management of these patients. An anonymous web-based survey was distributed to several listservs for pediatric cardiologists and pediatric cardiothoracic surgeons. Survey questions targeted respondent practice characteristics, testing obtained, and indications for testing or surgical referral. In total 61 responses were received, predominantly from pediatric cardiologists (95%) in the United States (97%). About 60% of clinicians reported frequently diagnosing patients with vascular rings by fetal echocardiogram, with only about 20% diagnosing them frequently on evaluation of symptoms. Computed tomography angiography and echocardiogram were the most common imaging modalities employed. Most clinicians obtained cross-sectional imaging at the time of diagnosis and referred to surgery once patients had at least occasional symptoms. Respondents demonstrated a low degree of agreement (Krippendorf's alpha 0.48). Few statistically significant patterns were identified between respondents based on their practice characteristics. This study identified significant variation between clinicians regarding the evaluation and management of vascular rings. Further research or expert opinions may help to standardize practice, saving costs and improving the quality of care for affected patients.

Persistence of aerodigestive symptoms after vascular ring repair.

OBJECTIVE: Vascular rings are often associated with respiratory and swallowing difficulties due to tracheal or esophageal compression. While the results of a vascular ring repair are considered excellent, the long-term effect of tracheal and esophageal remodeling and the persistence of symptoms have scarcely been reported. Our study aims to evaluate the respiratory and swallowing outcomes of vascular ring repair. STUDY DESIGN AND METHODS: A retrospective cohort study of children who underwent vascular ring repair between 2010 and 2022 in a tertiary-care children's hospital. RESULTS: There were 108 patients enrolled: sixty-three patients (57.41 %) with a right aortic arch, 42 patients (38.89 %) with a double aortic arch, and 3 patients (2.78 %) with other vascular rings. Forty-three (39.81 %) patients were diagnosed prenatally. Of the 65 patients (60.19 %) diagnosed postnatally, 35/65 (53.85 %) had either respiratory or swallowing symptoms as the indication for diagnostic workup. Persistent respiratory and swallowing symptoms were noted in 34/108 (31.48 %) and 30/108 (27.78 %) patients, respectively, within a year of surgical repair. Fourteen patients underwent repeated laryngoscopy and bronchoscopy that demonstrated residual tracheomalacia; however, only 2/14 (1.9 %) patients required tracheostomy tube placement, and 6-out-of-7 patients were weaned off positive pressure airway support. Persistent respiratory symptoms were significantly more common in patients with a double aortic arch compared to a right aortic arch. No differences were noted in demographics, comorbidities, and preoperative aerodigestive symptoms between patients with residual symptoms and patients with no residual symptoms. CONCLUSIONS: Persistent respiratory and swallowing symptoms after vascular ring repair are not uncommon. Postoperative evaluation should be pursued by a dedicated team, and treatment considered as appropriate.

Aberrant right subclavian artery intervention can provide relief of dysphagia.

BACKGROUND: An aberrant right subclavian artery represents the most common aortic arch vascular anomaly. Conventional wisdom states that these anomalies do not result in dysphagia, but rather serve as "red herrings". Clearly, in the vast majority of cases, this holds true. Nonetheless, one should never say never. METHODS: Herein, we present a cohort of four children with debilitating dysphagia resulting from an aberrant right subclavian artery. Subclavian reimplantation via a right posterolateral thoracotomy was performed successfully in all cases. RESULTS: Dysphagia resolved postoperatively, and all patients were able to advance to a normal diet. They were able to gain appropriate weight postoperatively and continue to do well at most recent clinical follow-up. CONCLUSIONS: This case series suggests that aberrant right subclavian artery anatomy should be considered a potential aetiology of dysphagia, albeit rarely. Surgical intervention for select patients can provide dramatic resolution of symptoms.

Left aortic arch and aberrant right subclavian artery in children: spectrum of symptoms and response to surgical intervention.

BACKGROUND: Children with left aortic arch and aberrant right subclavian artery may present with either respiratory or swallowing symptoms beyond the classically described solid-food dysphagia. We describe the clinical features and outcomes of children undergoing surgical repair of an aberrant right subclavian artery. MATERIALS AND METHODS: This was a retrospective review of children undergoing repair of an aberrant right subclavian artery between 2017 and 2022. Primary outcome was symptom improvement. Pre- and post-operative questionnaires were used to assess dysphagia (PEDI-EAT-10) and respiratory symptoms (PEDI-TBM-7). Paired t-test and Fisher's exact test were used to analyse symptom resolution. Secondary outcomes included perioperative outcomes, complications, and length of stay. RESULTS: Twenty children, median age 2 years (IQR 1-11), were included. All presented with swallowing symptoms, and 14 (70%) also experienced respiratory symptoms. Statistically significant improvements in symptoms were reported for both respiratory and swallowing symptoms. Paired (pre- and post-op) PEDI-EAT-10 and PEDI-TBM-7 scores were obtained for nine patients, resulting in mean (± SD) scores decreasing (improvement in symptoms) from 19.9 (± 9.3) to 2.4 (± 2.5) p = 0.001, and 8.7 (± 4.7) to 2.8 (± 4.0) p = 0.006, respectively. Reoperation was required in one patient due to persistent dysphagia from an oesophageal stricture. Other complications included lymphatic drainage (n = 4) and transient left vocal cord hypomobility (n = 1). CONCLUSION: Children with a left aortic arch with aberrant right subclavian artery can present with oesophageal and respiratory symptoms beyond solid food dysphagia. A thorough multidisciplinary evaluation is imperative to identify patients who can benefit from surgical repair, which appears to be safe and effective.

[Right aortic arch with mirror image branching : a rare cause of dysphagia]. / L'image du mois. Arc aortique droit avec image en miroir : une cause rare de dysphagie.

We report the case of a 36-year-old female whose dysphagia revealed a congenital anomaly of the thoracic aorta: the right aortic arch with mirror image branching. This is a rare embryonic developmental anomaly where the aorta wraps around the right bronchus and the supra-aortic trunks emerge from the arch in the opposite order to normal. Most of the patients are asymptomatic unless there is a significant compression of mediastinal structures. Major compression of the esophagus or trachea, aneurysmal disease, dissection of the thoracic aorta, or the presence of a Kommerell diverticulum larger than 2 cm may require a surgical repair. There is no standard treatment and it must be adapted to the clinical presentation and the anatomic configuration of each patient. Our patient did not receive any treatment for her condition.

Nous rapportons le cas d'une patiente de 36 ans dont le tableau de dysphagie a permis de mettre en évidence une anomalie congénitale de l'aorte thoracique : l'arc aortique droit avec image en miroir. Il s'agit d'une anomalie de développement embryonnaire rare où l'aorte s'enroule autour de la bronche souche droite et où les troncs supra-aortiques émergent de la crosse dans l'ordre inverse et opposé à la normale. La grande majorité des patients est asymptomatique, à moins qu'il existe une compression des structures médiastinales. Une compression majeure de l'oesophage ou de la trachée, une maladie anévrismale, une dissection de l'aorte thoracique ou la présence d'un diverticule de Kommerell de plus de 2 cm peuvent justifier une sanction chirurgicale. Il n'y a pas de traitement standard et celui-ci doit être adapté à la présentation clinique et à la configuration anatomique du patient. Notre patiente n'a bénéficié d'aucun traitement pour son affection.

Double aortic arch: implications of antenatal diagnosis, differential growth of arches during pregnancy, associated abnormalities and postnatal outcome.

OBJECTIVES: To evaluate the prenatal characteristics of double aortic arch (DAA), assess the relative size of the arches and their growth during pregnancy, describe associated cardiac, extracardiac and chromosomal/genetic abnormalities and review postnatal presentation and clinical outcome. METHODS: This was a retrospective cohort study of all fetuses with a confirmed diagnosis of DAA seen in five specialized referral centers in London, UK, between October 2012 and November 2019. Cases were identified from the hospitals' fetal databases. Fetal echocardiographic findings, intracardiac and extracardiac abnormalities, genetic defects, computed tomography (CT) findings and postnatal clinical presentation and outcome were evaluated. RESULTS: A total of 79 fetuses with DAA were included. Of those assessed postnatally, 48.6% had an atretic left aortic arch (LAA), while 5.1% had an atretic LAA at the first fetal scan and were misdiagnosed antenatally with right aortic arch (RAA). The LAA was atretic in 55.8% of those who underwent CT. DAA was an isolated abnormality in 91.1% of cases; 8.9% of patients had an additional intracardiac abnormality and 2.5% had both intra- and extracardiac abnormalities. Among the 52 cases that underwent genetic testing, 11.5% had genetic abnormalities and, specifically, the 22q11 microdeletion was identified in 3.8% of patients. At a median follow-up of 993.5 days, 42.5% of patients had developed symptoms of tracheoesophageal compression (5.5% during the first month after birth) and 56.2% had undergone intervention. Statistical analysis using the χ-square test showed no significant relationship between morphology of DAA (patency of both aortic arches vs atretic LAA) and the need for intervention (P = 0.134), development of vascular ring symptoms (P = 0.350) or evidence of airway compression on CT (P = 0.193). CONCLUSIONS: Most cases of DAA can be diagnosed easily at midgestation, as typically both arches are patent with a dominant RAA at this stage. However, we found that the LAA had become atretic in approximately half of the cases postnatally, supporting the theory of differential growth of the arches during pregnancy. DAA is usually an isolated abnormality; however, thorough assessment is required to exclude associated intra- and extracardiac anomalies and to determine the need for invasive prenatal genetic testing. Postnatally, early clinical assessment is needed and CT scan should be considered, irrespective of the presence of symptoms. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Vascular ring: prenatal diagnosis and prognostic management based on sequential cross-sectional scanning by ultrasound.

BACKGROUND: In terms of embryonic origin, vascular ring is a congenital anomaly in which the aortic arch and its branches completely or incompletely encircle and compress the trachea or esophagus. Early and accurate diagnosis of a vascular ring is the key to treatment. Prenatal diagnosis mainly relies on fetal echocardiography, but the rate of missed diagnosis and misdiagnosis is still very high, and the prognosis has not been evaluated. The aim of this study was to investigate the accuracy of prenatal diagnosis and to evaluate the prognosis semi-quantitatively according to the shape of the ring and the distance between the vessel and the trachea. METHODS: From 2019 to 2021, 37,875 fetuses underwent prenatal ultrasound examination in our center. All fetal cardiac examinations were performed using the fetal echocardiography method proposed by the American Institute of Ultrasound in Medicine (AIUM) combined with dynamic sequential cross-sectional observation (SCS). For SCS, the standard abdominal section was taken as the initial section, and the probe was moved cephalically along the long axis of the body until the superior mediastinum had disappeared. If a vascular ring was found, the shape of the ring and the distance of the branch to the airway were observed. The distance relationship with the airway was divided into three grades: I-III; the closer the distance, the lower the grade. The vascular rings were monitored every 4 weeks before birth. All were monitored before surgery or 1 year after birth. RESULTS: A total of 418 cases of vascular rings were detected. There was no missed diagnoses or misdiagnoses by SCS. The vessels formed different shaped rings according to their origin and route. Grade I, "" and "O" rings have a poor prognosis and are associated with the highest risk of respiratory symptoms. CONCLUSIONS: SCS can accurately diagnose vascular rings before delivery, evaluate the shape and size of the rings to conduct prenatal monitoring of children until birth, which plays a guiding role in airway compression after birth.

The ductus arteriosus: a review of embryology to intervention.

This article reviews the physiology of the ductus arteriosus, the pathophysiology of the patent ductus arteriosus (PDA), and the role advanced imaging such as computed tomography (CT) and magnetic resonance imaging (MRI) can play in guiding diagnosis and percutaneous or surgical intervention. A PDA can have variable clinical and radiologic presentations and can be important to characterize in patients with vascular rings, aortic maldevelopment and congenital heart disease. An understanding of the PDA and the application of CT and MRI can allow the radiologist to provide key information to physicians who plan to close a PDA or maintain PDA patency in the setting of ductal-dependent congenital heart disease.

Double Aortic Arch with Atresia of the Left Aortic Arch Proximal to the Left Common Carotid Artery: First Report of Documentation by Surgical Observation.

Double aortic arch associated with atresia of the left arch proximal to the left common carotid artery has been considered a theoretical possibility. To our knowledge, we report the first patient with this anatomy confirmed by surgical observation.

Unusual Vascular Ring in the Fetus.

We present the clinical course and echocardiographic and genetic findings of two fetuses with an unusual vascular ring, created by a left aortic arch with a right arterial duct and an aberrant right subclavian artery. One fetus was diagnosed with 22q11.2 microdeletion and the other became symptomatic in infancy. It is important to consider the position of the arterial ductal ligament in patients who present with tracheoesophageal compressive symptoms in the presence of a left aortic arch. These cases also highlight that a vascular ring formed from a left arch may have similar associations to a vascular ring formed by a right aortic arch.

Contemporary Outcomes in Fetuses Diagnosed with Vascular Rings.

Vascular rings are increasingly identified on fetal echocardiography. The purpose of this study is to analyze clinical outcomes and patterns of diagnostic testing in fetuses with vascular rings diagnosed by echocardiography. A retrospective cohort study was performed of fetuses with postnatally confirmed vascular rings from 2017 to 2022. Clinical outcomes included type and timing of symptoms, and timing of surgical intervention. Freedom from symptoms and/or surgery was assessed by Kaplan-Meier analysis. Frequency of genetic and diagnostic testing (barium esophagogram, CT/MRI angiogram, and bronchoscopy) was also assessed. Overall, 46 patients were evaluated (91% with a right aortic arch/left ductus and 4% with a double aortic arch). A vascular ring was isolated in 59%, associated with structural heart lesions in 33%, and associated with noncardiac anomalies in 8%. Prenatal diagnoses increased over time. Symptoms developed in 24% (11/46); 82% (9/11) had respiratory and 45% (5/11) had gastroesophageal complaints. Surgery was performed in 17% (11/46). Symptoms presented bimodally, prior to 100 or after 400 days of life. There was no difference in the type of symptoms for early (< 100 days) or late (> 400 days) presenters. Symptomatic patients received more diagnostic testing. Genetic testing was obtained in 46% and positive in 33%, with 22q11 deletion and Trisomy 21 being identified. Prenatal diagnoses of vascular rings increased over time, with subjects developing symptoms bimodally in early or late infancy. The frequency of genetic testing was suboptimal given the prevalence of genetic abnormalities seen in this population.

Recognising ligamentous atresia in double aortic arch.

Ligamentous atresia of the left side of a double arch distal to the left subclavian artery is a rare form of vascular ring, which can easily be confused, on transthoracic echocardiography, with the right-sided aortic arch when there is mirror-imaged branching. Because of its rapid acquisition, computed tomographic angiography with three-dimensional reconstruction has now become the modality of choice for accurate diagnosis of the various forms of double aortic arch. It can be performed without sedation in any age group, including neonates. It provides excellent visualisation of the aortic arch and its branching pattern, thus permitting accurate diagnosis and surgical planning. We present a case series of six children with this rare vascular ring assessed using CT, highlighting their outcomes.

Management of prenatally detected vascular rings: a United Kingdom national survey.

OBJECTIVE: To investigate UK variability in prenatal and postnatal management strategy of right aortic arch and double aortic arch (RAA/DAA). METHODS: Online surveys were sent to senior physicians (consultants) of the National Fetal Cardiology Working Group regarding prenatal diagnosis, counselling, and perinatal management of antenatally diagnosed RAA/DAA and to the British Congenital Cardiovascular Association regarding postnatal management strategies. RESULTS: There were 28 prenatal and 90 postnatal surveys completed. Prenatally, there was consensus for potential associated chromosomal/genetic anomalies, but there was variation in the risk quoted. Confidence in defining aortic arch morphology was reported by 43% (12/28) of fetal cardiologists. There was variation in what was felt to be possible symptoms/signs of a compressive vascular ring, postnatal investigation, postnatal management, follow-up duration of asymptomatic patients, and indications for surgical intervention. CONCLUSION: This study has highlighted important areas for future research: improving accuracy of prenatal diagnosis, clarification of potential symptoms, optimal investigation strategies, and indications for surgery.

The Impact of Prenatal Diagnosis on Clinical Outcomes of Isolated Vascular Rings From a Statewide Paediatric Cardiology Tertiary Service.

BACKGROUND: Vascular rings, including right aortic arch with aberrant left subclavian artery (RAA-ALSCA), double aortic arch (DAA) and pulmonary artery sling (PAS), are congenital anomalies that may cause airway and oesophageal compression. As prenatal detection has improved, literature comparing clinical outcomes of antenatally versus postnatally diagnosed cases continues to emerge. The aim is to define a statewide tertiary paediatric institution's clinical profile and outcomes of prenatal versus postnatally diagnosed isolated vascular rings. METHOD: A retrospective single-centre review of isolated RAA-ALSCA, DAA and PAS between 1 January 1999 and 31 December 2020 was conducted. Clinical characteristics, surgical and follow-up information were collected. Antenatal and postnatally diagnosed groups were compared. RESULTS: Out of 123 cases diagnosed with isolated vascular rings, 98 (79.7%) cases had RAA-ALSCA, 21 (17.1%) with DAA, 4 (3.3%) with PAS. The antenatal detection rate was 73.6% in the past decade; 20.3% had a genetic disorder, of which 48% had 22q11.21 microdeletion. Of prenatally diagnosed cases, 31.3% developed symptoms, commonly stridor and dysphagia, at a median age of 2.0 months (IQR 0.0-3.0), compared to a median age of diagnosis for the postnatal cohort of 9 months (IQR 1.0-40.7). Postnatally diagnosed cases were more likely to present with symptoms, primarily respiratory distress, than prenatally diagnosed cases (p=0.006). Fifty-nine (59) cases (50% antenatally diagnosed) required vascular ring division; 6.8% had residual symptoms following surgery. DISCUSSION: Antenatal diagnosis has improved and leads to better parental awareness and more timely, appropriate intervention. Postnatally diagnosed patients were older, more likely to be symptomatic, underwent more investigations and were commenced on more medications for symptom management prior to diagnosis. One in five cases of isolated vascular ring anomalies carried a genetic diagnosis, which has important implications on prenatal counselling and genetic testing.

Computed tomographic features of double aortic arch in six dogs.

Double aortic arch (DAA) is a rare, congenital anomaly in small animals, resulting in a complete vascular ring encircling the esophagus and trachea, and subsequent compression of these organs. Few studies have reported utilizing CT angiography (CTA) for diagnosing DAA in dogs; thus, the imaging features are currently lacking in the literature. The objectives of this retrospective, multicenter, descriptive case series were to report the clinical and CTA characteristics of DAA in surgically treated cases. Medical records and CTA images were reviewed. Six juvenile dogs met the inclusion criteria (median age: 4.2 months; range: 2-5 months). The most common clinical signs included chronic regurgitation (100%), decreased body condition (67%), and coughing (50%). Common CTA features of DAA included a dominant left aortic arch (median diameter: 8.1 mm) and minor right aortic arch (median diameter: 4.3 mm; 83%), an aberrant right subclavian artery arising directly from the right aortic arch (83%), segmental esophageal constriction (100%), and variable degrees of dilation cranial to the heart base, and marked tracheal luminal compression (median percent change: -55%; 100%) and leftward curvature of the trachea at the level of the bifurcation of the aortic arches (100%). All dogs underwent successful surgical correction with only minor postoperative complications. Due to the similarity of clinical and imaging characteristics described to that of other forms of vascular ring anomalies (VRA), CTA is vital for the specific diagnosis of DAA in dogs.