Superior epigastric artery

In human anatomy, the superior epigastric artery is a terminal  branch of the internal thoracic artery that provides arterial supply to the abdominal wall, and upper rectus abdominis muscle. It enters the rectus sheath to descend upon the inner surface of the rectus abdominis muscle. It ends by anastomosing with the inferior epigastric artery.

Origin
The superior epigastric artery arises from the internal thoracic artery (referred to as the internal mammary artery in the accompanying diagram).

Course and relations
The superior epigastric artery pierces the diaphragm  to enter the rectus sheath and descend upon the deep surface of the rectus abdominis.

Along its course, it is accompanied by a similarly named vein, the superior epigastric vein.

Anastomoses
It anastomoses with the inferior epigastric artery within the rectus abdominis muscle   at the umbilicus.

Distribution
Where it anastomoses, the superior epigastric artery supplies the anterior part of the abdominal wall, upper rectus abdominis muscle, and some of the diaphragm.

Vascular disease
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.

Coarctation of the aorta
A congenitally narrowed aorta, due to coarctation, is often associated with a significant enlargement of the internal thoracic and epigastric arteries.