Double aortic arch (Human Phenotype Ontology id HP_0011590) is a conenital abnormality of the aortic arch in which the two embryonic aortc arches form a vascular ring that surrounds the trachea or esophagus and then join to form the descending aorta. Double aortic arch can cause symptoms because of compression of the esophagus (dysphagia, cyanosis while eating) or trachea (stridor).