Embryology and Imaging Review of Aortic Arch Anomalies

Confusion from prenatal diagnosis: Type C persistent fifth aortic arch or right-side ductus arteriosus

We described a case of a double aortic arch (DAA) with a subaortic left brachiocephalic vein (LBCV) and right-side ductus arteriosus using high-definition (HD) flow render mode and spatiotemporal image correlation (STIC). We experienced uncertainty regarding this interesting case despite the diagnosis of right-sided ductus arteriosus. The ductus arteriosus originates from the right pulmonary artery (PA) and converges into the descending aorta (DAO), whereas the vessel originated from the PA and converged into the ascending aorta (AAO). Therefore, we assumed that the vessel connecting the PA to AAO may be a type-C persistent fifth aortic arch (PFAA).

International Multi-Institutional Experience with Presentation and Management of Aortic Arch Laterality in Aberrant Subclavian Artery and Kommerell's Diverticulum

BACKGROUND

Aberrant subclavian artery (ASA) with or without Kommerell's diverticulum (KD) is a rare anatomic aortic arch anomaly that can cause dysphagia and/or life-threatening rupture. The objective of this study is to compare outcomes of ASA/KD repair in patients with a left versus right aortic arch.

METHODS

Using the Vascular Low Frequency Disease Consortium methodology, a retrospective review was performed of patients ≥18 years old with surgical treatment of ASA/KD from 2000 to 2020 at 20 institutions.

RESULTS

288 patients with ASA with or without KD were identified; 222 left-sided aortic arch (LAA), and 66 right-sided aortic arch (RAA). Mean age at repair was younger in LAA 54 vs. 58 years (P = 0.06). Patients in RAA were more likely to undergo repair due to symptoms (72.7% vs. 55.9%, P = 0.01), and more likely to present with dysphagia (57.6% vs. 39.1%, P < 0.01). The hybrid open/endovascular approach was the most common repair type in both groups. Rates of intraoperative complications, death within 30 days, return to the operating room, symptom relief and endoleaks were not significantly different. For patients with symptom status follow-up data, in LAA, 61.7% had complete relief, 34.0% had partial relief and 4.3% had no change. In RAA, 60.7% had complete relief, 34.4% had partial relief and 4.9% had no change.

CONCLUSIONS

In patients with ASA/KD, RAA patients were less common than LAA, presented more frequently with dysphagia, had symptoms as an indication for intervention, and underwent treatment at a younger age. Open, endovascular and hybrid repair approaches appear equally effective, regardless of arch laterality.

Subclavian steal syndrome in a right aortic arch with aberrant left subclavian artery atresia

Congenital aortic arch anomalies are an uncommon diagnosis resulting from embryologic malformations during the fourth to eighth week of gestation. Asymptomatic variants frequently are overlooked in the perinatal period and diagnosed incidentally during adulthood. Symptomatic variants can present with steal syndrome or dysphagia lusoria. The right aortic arch is a rare anomaly that is usually associated with other congenital anomalies but can occur in isolation. The most common types of right aortic arches are mirror image branching or an aberrant left subclavian artery. Aortic arch anomalies are important to recognize as they may have important implications in management. We present a 74-year-old female with a right aortic arch and aberrant left subclavian artery that was discovered after a fall. An extensive evaluation and work-up revealed symptoms consistent with subclavian steal syndrome that resolved following a carotid-axillary bypass. Subclavian steal secondary to a right aortic arch is extremely rare. This report reviews the current literature of a right aortic arch with an aberrant left subclavian artery presenting as a subclavian steal syndrome.

Congenital Anomalies of Aortic Arch: A Pictorial Essay

Aortic abnormalities account for 15 to 20% of all congenital cardiovascular diseases. The purpose of this pictorial essay is to illustrate various congenital anomalies of the aortic arch, which influence patient management and outcome.

High heritability of ascending aortic diameter and trans-ancestry prediction of thoracic aortic disease

Enlargement of the aorta is an important risk factor for aortic aneurysm and dissection, a leading cause of morbidity in the developed world. Here we performed automated extraction of ascending aortic diameter from cardiac magnetic resonance images of 36,021 individuals from the UK Biobank, followed by genome-wide association. We identified lead variants across 41 loci, including genes related to cardiovascular development (HAND2, TBX20) and Mendelian forms of thoracic aortic disease (ELN, FBN1). A polygenic score significantly predicted prevalent risk of thoracic aortic aneurysm and the need for surgical intervention for patients with thoracic aneurysm across multiple ancestries within the UK Biobank, FinnGen, the Penn Medicine Biobank and the Million Veterans Program (MVP). Additionally, we highlight the primary causal role of blood pressure in reducing aortic dilation using Mendelian randomization. Overall, our findings provide a roadmap for using genetic determinants of human anatomy to understand cardiovascular development while improving prediction of diseases of the thoracic aorta.

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.

Kommerell’s diverticulum with right-sided aortic arch and anomalous origin of neck vessels: Uncommon imaging finding in neonate with cyanosis

Kommerell diverticulum is a rare developmental anomaly of aortic arch. It is most frequently seen with right-sided aortic arch and aberrant left subclavian artery or ligamentum arteriosum, which have a significant role in completing a vascular ring. However, aberrant origin of neck vessels along with it is not commonly seen. The signs and symptoms vary depending on the severity. The paediatric patients usually present early due to compression of mediastinal structures such as trachea or oesophagus.

Pulmonary Manifestations of Congenital Heart Disease in Children

This review addresses how anomalous cardiovascular anatomy imparts consequences to the airway, respiratory system mechanics, pulmonary vascular system, and lymphatic system. Abnormal formation or enlargement of great vessels can compress airways and cause large and small airway obstructions. Alterations in pulmonary blood flow associated with congenital heart disease (CHD) can cause abnormalities in pulmonary mechanics and limitation of exercise. CHD can lead to pulmonary arterial hypertension. Lymphatic abnormalities associated with CHD can cause pulmonary edema, chylothorax, or plastic bronchitis. Understanding how the cardiovascular system has an impact on pulmonary growth and function can help determine options and timing of intervention.

Anomalous origin of left subclavian artery from ascending aorta in a right aortic arch: A case report with review of literature

We present a case of an 11-year-old boy with a double-outlet right ventricle and a right-sided aortic arch showing anomalous origin of the left subclavian artery from the ascending aorta as the first branch. This case highlights the importance of knowledge of this aberrant anatomy before planning any surgical or endovascular intervention.

New findings of branching variations in subclavian arteries and supra-aortic arteries in Felis catus

The branching of blood vessels around the heart is varied in each animal. Three branching patterns of the brachiocephalic trunk in cats have been reported. However, supra-aortic arteries in the hearts of cats have never been investigated. In this study, we hypothesized that the variations of the aortic arch, supra-aortic arteries, and vena cava were observed in domestic cats. Sixty-one hearts obtained from the cadavers of domestic cats (Felis catus) were analyzed in terms of anatomical characteristics, size, and the length of these supra-aortic vessels by using a 3D scanner. New variations of the left and right subclavian arteries were observed using the location of the internal thoracic (ITA) and vertebral artery (VA) as the criterion to group the varying patterns. We found four patterns of the left subclavian artery, which included ITA budding contralateral before VA (5%), VA budding opposite to ITA (75%), VA budding contralateral before ITA (13%) and ITA budding ipsilateral before VA (7%). In contrast, only three patterns were found in the right subclavian artery, which included VA budding opposite to ITA (20%), VA budding contralateral before ITA (19%), and ITA budding contralateral before VA (61%). Moreover, although an average vascular diameter in male cats was higher than in female subjects, the supra-aortic blood volume in both sexes was not different. The findings of this study could help fill the existing gap of knowledge on the anatomical variations of supra-aortic arteries in cats and could be used in clinical applications based on relevant anatomical data.

320-slice Computed Tomography Angiography Imaging Findings and Follow-up in A Patient with Aortic Coarctation Misdiagnosed as Hypertension: A Case Report and Literature Review

In this case, we report a simple coarctation of the aortic isthmus (CoA) in a patient without intracardiac abnormalities or patent ductus arteriosus, who was misdiagnosed as essential hypertension for over 20 years. The patient underwent X-rays, echocardiography, and 320-slice CT angiography (CTA). Among them, CTA comprehensively showed the diameter of the aortic coarctation, the anatomy and morphology of the heart and aortic arch, and the collateral circulation before surgery. It also accurately evaluated the postoperative status of the bypass vessel. This article highlights the excellent performance of 320-slice CTA in the diagnosis, surgical planning, and follow-up in CoA. Moreover, when adolescents suffer from refractory hypertension, the possibility of organic cardiovascular disease should be considered.

Prevalence and Types of Aortic Arch Variants and Anomalies in Congenital Heart Diseases

RATIONALE AND OBJECTIVES

Aortic arch (AA) variants and anomalies are important to recognize in patients with congenital heart disease (CHD) before surgery or intervention. The aim was to study the prevalence of AA anomalies and variants in patients with CHD compared to a control group. The secondary outcome was to report the associations between common variations of AA and specific types of CHD.

MATERIALS AND METHODS

After institutional review board approval, computed tomography studies of 352 CHD patients and control group of 400 consecutive computed tomography scans of the thorax were evaluated. The AA was assigned to one of seven common types, and their distribution was compared between CHD and control. The distribution of the AA anomalies and variants was evaluated as regard specific types of CHD and the visceroatrial situs.

RESULTS

Normal three-vessel branching pattern was the commonest in both groups, but was present in only 50.5% in the CHD compared to 68.5% in the control group, p < 0.00001. Right AA and aberrant right subclavian artery were significantly more common in CHD than control group (18.1% versus 0.25%, p < 0.00001) and (4.5% versus 0.25%, p = 0.0001), respectively. Direct aortic origin of left vertebral artery was insignificantly more common in CHD group (4.2% versus 2.7%, p = 0.258). Brachiobicephalic trunk was significantly more common in control than CHD group (27.7% versus 19.3%, p = 0.007).

CONCLUSION

Normal three-vessel AA was significantly less common in CHD. AA anomalies (right arch and aberrant right subclavian) were more common in CHD than control, while AA variants (brachiobicephalic trunk and direct aortic origin of left vertebral artery) were not.

Ductus arteriosus location in relation to aortic arch position, branching pattern, and viscero-atrial situs

AIM

To investigate ductus arteriosus (DA) location in relation to viscero-atrial situs and branching pattern of the right aortic arch (RAA).

MATERIALS AND METHODS

Computed tomography (CT) images of paediatric patients (May 2015 to July 2017, n=352) referred for evaluation of cardiovascular malformations were reviewed retrospectively. Patients with RAA were identified and images were analysed for documentation of the viscero-atrial situs, the branching pattern, DA location, and associated malformations.

RESULTS

The study included 64 RAA patients, 45 situs solitus, 11 situs ambiguous, and eight situs inversus. Mirror-image branching was observed in 34 situs solitus, 11 situs ambiguous, and seven situs inversus patients. Aberrant left subclavian artery (ALSCA) was present in 10 situs solitus and one situs inversus patient. One patient with situs solitus had isolated left subclavian artery. The location of the DA was identifiable in 32 patients (19 left and 13 right). In situs solitus with mirror-image branching, the DA was left in 10, right in four patients. In situs inversus and ambiguous with mirror-image branching, the DA was right in eight and left in two patients. In patients with ALSCA, the DA was left in seven and right in one patient. The location of the DA was identifiable in 85 patients with left aortic arch (left-sided in 84, right-sided in only one patient).

CONCLUSION

The location of DA in RAA varies according to viscero-atrial situs and branching pattern. In mirror-image branching, the DA is more commonly left-sided with situs solitus and more right-sided with abnormal viscero-atrial situs.

Aortic Arch Variants: A Practical Guide to Safe and Timely Catheterization

Background

Variations in aortic arch anatomy have been extensively described from multiple perspectives including gross anatomy, embryology, associated cardiac and other anomalies, early life presentation, and cross-sectional diagnosis. There is however a paucity of literature with an emphasis on safe and timely catheterization, particularly when the variants are found during emergent or other catheter angiographic procedures without benefit of prior cross-sectional vascular imaging. The purpose of this review is to try to fill this gap.

Methods

A review of past 1,000 diagnostic and therapeutic catheterizations was performed to identify arch variants, which are presented in order of frequency encountered at our institutions.

Results

The variants are presented as illustrations and catheter angiographic images, with emphasis on safe and efficient intraprocedural diagnosis and catheterization.

Conclusion

Familiarity with more and less common arch variants, along with low threshold for performance of pigtail aortic arch angiography and comfort in use of general purpose and recurved catheters, will ensure success in the vast majority of encountered variations.

Routine multi detector computed tomography evaluation of tracheal impairment compared to laryngo-tracheal endoscopy in children with vascular ring

PURPOSE

The aim of this study is to compare free-breathing routine multi detector computed tomography (MDCT) and laryngo-tracheal (LT) flexible endoscopy in the evaluation of tracheal impairment in children with vascular ring (VR).

MATERIALS AND METHODS

We performed a retrospective and monocentric study of all patients with VR from 1997 to 2014. Clinical data included: initial symptoms, type of surgery and clinical outcome. MDCT were blindly reviewed by two radiologists in consensus, independently of LT endoscopy results. Radiologic and endoscopic results were reviewed according to four criteria: percentage of tracheal narrowing, distance of the compression from carina, presence of bronchial compression and signs of tracheomalacia (TM). Concordance was evaluated for each criterion with a Spearman coefficient.

RESULTS

From 1997 to 2016, 21 patients with a vascular ring were operated on, among which 57% by thoracoscopy: double aortic arch (n = 14), Neuhauser anomaly (n = 4) and Right aorta + aberrant right subclavian artery (n = 3). 90% of them presented with respiratory symptoms among which 43% of stridor. Chest X-ray was suggestive of VR in 87% of the cases. MDCT images and LT endoscopy results were available and analyzed for nine patients. Concordance (Spearman correlation coefficient) was excellent for percentage and level of tracheal narrowing (1) and good for TM (0.79).

CONCLUSION

Free breathing routine MDCT is a reliable exam compared to LT endoscopy in the evaluation of tracheal impairment in children with VR. In case of respiratory symptoms (except stridor) and suggestive chest X-ray of VR, endoscopy could be avoided and routine MDCT alone performed.

Aortopexy for Life-Threatening Airway Obstruction Following Division of Double Aortic Arch

Symptoms of airway compression secondary to double aortic arch are relieved by division of one of the two aortic arches. However, in some cases inherent tracheomalacia and other factors may result in persistence of symptoms. We report one such occurrence in our experience and describe the use of aortopexy as a curative procedure to tackle this problem.

Thrombosis of Kommerell's diverticulum with subclavian steal phenomenon in a patient with non-small cell lung carcinoma under chemotherapy

Kommerell’s diverticulum (KD) is defined as a bulbous dilatation of the origin of an aberrant subclavian artery due to a remnant of the left fourth aortic arch. We report the case of an asymptomatic woman in whom progressive thrombosis of the KD extending to the prevertebral tract of an aberrant right subclavian artery was detected at multidetector computed tomography imaging for lung cancer staging performed before and after the beginning of chemotherapy. Reversed blood flow in the ipsilateral vertebral artery due to subclavian steal phenomenon was also observed by color Doppler ultrasound examination.

Right aortic arch with aberrant left innominate artery arising from Kommerell's diverticulum

We report a case of an uncommon thoracic aorta anomaly-right aortic arch with aberrant left innominate artery arising from Kommerell's diverticulum-that went undiagnosed until adulthood.

Outcomes After Operations for Unicuspid Aortic Valve With or Without Ascending Repair in Adults

BACKGROUND

Unicuspid aortic valve is an important subset of bicuspid aortic valve, and knowledge regarding its aortopathy pattern and surgical outcomes is limited. Our objectives were to characterize unicuspid aortic valve patients, associated aortopathy, and surgical outcomes.

METHODS

From January 1990 to May 2013, 149 adult unicuspid aortic valve patients underwent aortic valve replacement or repair for aortic stenosis (n = 13), regurgitation (n = 13), or both (n = 123), and in 91 (61%) the aortic valve operation was combined with aortic repair. Data were obtained from the Cardiovascular Information Registry and medical record review. Three-dimensional imaging analysis was performed from preoperative computed tomography and magnetic resonance imaging scans. The Kaplan-Meier method was used for survival analysis.

RESULTS

Patients had a mean maximum aortic diameter of 44 ± 8 mm and variably involved the aortic root, ascending, or arch, or both. Patients with valve operations alone were more likely to be hypertensive (p = 0.01) and to have severe aortic stenosis (p = 0.07) than those who underwent concurrent aortic operations. There were no operative deaths, strokes, or myocardial infarctions. Patients undergoing aortic repair had better long-term survival. Estimated survival at 1, 5, and 10 years was 100%, 100%, and 100% after combined operations and was 100%, 88%, and 88% after valve operations alone (p = 0.01).

CONCLUSIONS

Patients with a dysfunctional unicuspid aortic valve frequently present with an ascending aneurysm that requires repair. Combined aortic valve operations and aortic repair was associated with significantly better long-term survival than a valve operation alone. Further study of this association may direct decisions about timing of surgical intervention.

Double aortic arch associated with bronchopulmonary sequestration: a rare dual anomaly

We report two isolated and rare congenital malformations, namely double aortic arch and bronchopulmonary sequestration occurring as coexisting lesions in an infant. Clinical presentation leading up to a detailed anatomic diagnosis, using echocardiography and multidetector computerized tomographic angiographic imaging are described. To our knowledge, our patient is the second case reported with this dual pathology, making it an exceedingly rare occurrence.

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.

Truncus bicaroticus with aberrant right subclavian artery and origin of right vertebral from right common carotid artery

We describe a rare constellation of variant anatomy of the aortic arch branches, seen on a magnetic resonance angiographic examination during the course of investigation for recent onset memory loss in a 52-year-old patient. There was a common origin of both the common carotid arteries (CCA), the common trunk being the first major branch of the aortic arch, the right vertebral artery arising from the right CCA and the right subclavian artery arising as the last branch of the arch. In isolation, the three components of this constellation have been reported with different frequencies, but as per the authors' knowledge, this entire constellation has been rarely reported. We review the literature and propose an embryological mechanism for this variant anatomy.

Endovascular repair with the chimney technique for Stanford type B aortic dissection involving right-sided arch with mirror image branching

PURPOSE

To report endovascular repair with the chimney technique of type B aortic dissection involving a right-sided aortic arch (RAA).

CASE REPORTS

Two hypertensive men aged 48 and 42 years with symptoms of aortic dissection resistant to medical therapy underwent emergent thoracic endovascular aortic repair with the chimney technique to extend the proximal landing zones. Both patients had right-sided arches with mirror image branching. One patient required a bare metal chimney stent to maintain perfusion to the right subclavian artery, while the other patient had a chimney stent to revascularize the right common carotid artery. Short-term follow-up (1 year and 1 month, respectively) showed that there was positive aortic remodeling, and the chimney stents were patent.

CONCLUSION

Chimney TEVAR seems safe and effective for Stanford type B dissection in patients having RAA with mirror image branching and no sufficient proximal fixation zone.

An allelic series of mice reveals a role for RERE in the development of multiple organs affected in chromosome 1p36 deletions

Individuals with terminal and interstitial deletions of chromosome 1p36 have a spectrum of defects that includes eye anomalies, postnatal growth deficiency, structural brain anomalies, seizures, cognitive impairment, delayed motor development, behavior problems, hearing loss, cardiovascular malformations, cardiomyopathy, and renal anomalies. The proximal 1p36 genes that contribute to these defects have not been clearly delineated. The arginine-glutamic acid dipeptide (RE) repeats gene (RERE) is located in this region and encodes a nuclear receptor coregulator that plays a critical role in embryonic development as a positive regulator of retinoic acid signaling. Rere-null mice die of cardiac failure between E9.5 and E11.5. This limits their usefulness in studying the role of RERE in the latter stages of development and into adulthood. To overcome this limitation, we created an allelic series of RERE-deficient mice using an Rere-null allele, om, and a novel hypomorphic Rere allele, eyes3 (c.578T>C, p.Val193Ala), which we identified in an N-ethyl-N-nitrosourea (ENU)-based screen for autosomal recessive phenotypes. Analyses of these mice revealed microphthalmia, postnatal growth deficiency, brain hypoplasia, decreased numbers of neuronal nuclear antigen (NeuN)-positive hippocampal neurons, hearing loss, cardiovascular malformations–aortic arch anomalies, double outlet right ventricle, and transposition of the great arteries, and perimembranous ventricular septal defects–spontaneous development of cardiac fibrosis and renal agenesis. These findings suggest that RERE plays a critical role in the development and function of multiple organs including the eye, brain, inner ear, heart and kidney. It follows that haploinsufficiency of RERE may contribute–alone or in conjunction with other genetic, environmental, or stochastic factors–to the development of many of the phenotypes seen in individuals with terminal and interstitial deletions that include the proximal region of chromosome 1p36.