“Migrant” Ductal Tissue in the Aortic Arch

BACKGROUND: ). However, functional constriction caused by ectopic ductal tissue at atypical arch locations is rare and may mimic fixed coarctation. CASE SUMMARY: . Further imaging clarified the anatomy, and surgical excision of the transverse arch segment demonstrated ductal tissue on histopathology. DISCUSSION: This case illustrates a rare mechanism of prostaglandin-responsive arch obstruction caused by ectopic ductal tissue, highlighting the importance of dynamic prostaglandin testing and multimodality imaging in differentiating functional from fixed neonatal arch obstruction. NOVELTY: -responsive coarctation of the transverse aortic arch resulting from ectopic ductal tissue, anatomically separate from the native ductus arteriosus, confirmed on histopathology.