Symptomatic stenosis of left subclavian artery from Kommerell's diverticulum.

Patients with a right aortic arch frequently develop an aneurysm at the origin of the left subclavian artery, called Kommerell's diverticulum; it is a remnant of the left fourth aortic arch. These variants may occur in combination with congenital heart defects or they may be isolated. We report an extremely rare case of symptomatic stenotic origin of an aberrant left subclavian artery arising from a Kommerell's diverticulum in a 39-year-old man with right-sided aortic arch who had left upper limb pain and numbness on exercise. He was successfully treated by percutaneous angioplasty and primary stent implantation.