A rare association with patent ductus arteriosus.

Persistent fifth aortic arch (PFAA), also known as congenital double-lumen aortic arch, is a rare developmental anomaly of the aortic arch. A 5-month-old baby who presented with congestive cardiac failure was diagnosed to have a large patent ductus arteriosus with PFAA. Although this arch anomaly had no hemodynamic relevance in this case, preoperative diagnosis prevented surprises "on table.