The superior epigastric artery refers to a blood vessel that carries oxygenated blood and arises from the internal thoracic artery. It anastomoses with the inferior epigastric artery at the umbilicus and supplies the anterior part of the abdominal wall and some of the diaphragm.
The superior epigastric arteries, inferior epigastric arteries, internal thoracic arteries and left subclavian artery and right subclavian artery / brachiocephalic are collateral vessels to the thoracic aorta and abdominal aorta. If the abdominal aorta develops a significant stenosis and/or blockage (as may be caused by atherosclerosis), this collateral pathway may develop sufficiently, over time, to supply blood to the lower limbs.