No abstract

Right-sided aorta and ALSA indicate embryologic regression of the left fourth primitive aortic arch. The absence of Kommerell's diverticulum at the origin of the ALSA indicates the lack of high-pressure blood flow from the pulmonary artery to the ALSA through the ductus arteriosus during embryogenesis, suggesting the embryologic regression of the left sixth primitive aortic arch. The presence of all 3 radiologic features thus highly suggests the possibility of a LNRLN.