What abnormality is shown on this reconstructed CT image (Figure )?

Patent ductus arteriosus

Findings: There is a vascular structure connecting the inferior aspect of the posterior aortic arch and the main pulmonary artery consistent with a patent ductus arteriosus.A: The image shows a connection between the posterior aortic arch and the main pulmonary artery consistent with patent ductus arteriosus. In truncus arteriosus there is a single great vessel which is located over a ventricular septal defect. Two great vessels are shown in this case. B: The image shows a connection between the posterior aortic arch and the main pulmonary artery consistent with patent ductus arteriosus. The diverticulum of Kommerell occurs at the origin of an aberrant right subclavian artery arising from the aorta. There is normal great vessel anatomy in this case. C: The image shows a connection between the aorta and main pulmonary artery consistent with patent ductus arteriosus. D: The image shows a connection between the aorta and main pulmonary artery consistent with patent ductus arteriosus. The aorta is normal in appearance.