Circumflex aorta: An uncharted territory

Abstract

Background Vascular rings are aortic arch anomalies with a spectrum of manifestations ranging from asymptomatic lesions detected incidentally to an acute presentation secondary to tracheo-esophageal compression. Circumflex retro-esophageal aortic arch is an extreme form of true vascular ring. It remains an uncharted territory to many surgeons. Methods A comprehensive search of peer reviewed journals was completed based on the key words, “Circumflex aorta,” “Circumflex retro-esophageal aorta” and “circumflex arch” using Google scholar, Scholars Portal Journals and PubMed. The reference section for each article found was searched to obtain additional articles. Literature on the circumflex aorta was reviewed starting from the embryogenesis to the latest management strategies. Results Right circumflex aorta is more prevalent compared to left circumflex aorta. It can occur in isolation or in association with other intracardiac lesions. Mainly presents in children, however reported in adults too. The presentation may vary from asymptomatic lesion to acute respiratory distress secondary to airway compression. Computerized tomography (CT) and magnetic resonance imaging (MRI) are important tools in delineating the vascular anatomy. Aortic uncrossing is the definitive procedure. However, the role of concomitant tracheobronchopexy is emerging. Native tissue-to-tissue anastomosis is commonly preferred, but cases of extra-anatomic grafts are reported. Conclusion Circumflex aorta is amenable to complete repair. Preoperative delineation of anatomy is important for successful surgical outcome. Division of the retro-esophageal segment is crucial in relieving the compressive symptoms. In addition, tracheobronchopexy is helpful in addressing residual tracheomalacia but this accounts for a high-risk surgery.

A left circumflex aorta with a displaced thoracic duct in a 94-year-old male cadaver: a case report with discussion on embryology

“…If the ductus or ligamentum arteriosum is present on the right side, connecting the right sided descending aorta with the right pulmonary artery, a complete vascular ring develops [21]. However, if the ductus or ligamentum arteriosum is located on the left side, the vascular ring is incomplete [9], as found in the present case. Even though a LCA with a left patent ductus arteriosus does not form a complete vascular ring, it can still cause severe respiratory compression, as shown by Sheth et al [20] in a case of a 2-month-old patient whose left main bronchus was obstructed.…”

“…Various findings in individual cases make it troublesome for the clinical practitioners to assign a single, unified embryological defect responsible for the creation of the LCA. The description of the LCA's origin provided by Hanneman et al [8] and Haranal et al [9] with absent variant right subclavian artery resulting from the involution of the right aortic arch in its part between the right subclavian and the ductus arteriosus most certainly does not pertain to the current case. For that variation to occur, the typical left aortic arch would not be present, contrary to the present findings.…”

“…Anomalies of the aortic arch are often associated with the formation of a vascular ring, with the circumflex aorta being an extreme example of the latter [9]. The circumflex aorta is divided into two groups; a right circumflex aorta, and a left circumflex aorta.…”

“…On the other hand, the left circumflex aorta can appear with, or without an aberrant right subclavian artery. In many cases, a patent ductus arteriosus / ligamentum arteriosum together with a left, or right, circumflex aorta develops a true vascular ring [9].…”

“…Many other anomalies of the cardiovascular system can occur in individuals with a LCA. These consist namely of formation of a vascular ring and an aberrant right subclavian artery, amongst others [9,25]. Furthermore, the prevalence of additional cardiac anomalies in patients with a circumflex aorta is approximately 50% to 60% [21].…”