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

Abstract

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