Dysphagia lusoria: aberrant right subclavian artery with a Kommerell's diverticulum.

A retroesophageal right subclavian artery, the most common congenital aortic arch abnormality, is an unusual cause of dysphagia in adults. The embryologic abnormality of the aortic arch is involution of the fourth vascular arch, along with the right dorsal aorta, leaving the seventh intersegmental artery attached to the descending aorta. This persistent intersegmental artery assumes a retroesophageal position as it proceeds out of the thorax into the arm. Since compression of the esophagus by this right subclavian artery may produce dysphagia, the term "dysphagia lusoria" ("dysphagia by freak of nature"), has been used to describe the symptom complex. The presence of an aneurysm of the artery or Kommerell's diverticulum at its aortic origin is more likely to produce symptoms from esophageal compression. This case presents a middle aged adult with an associated Kommerell's diverticulum and dysphagia. Surgical correction was used to relieve his symptoms and to correct the diverticulum of the proximal right subclavian artery. The embryologic changes that occur are discussed in detail.