The Superior mesenteric artery is a branch of the abdominal aorta. It is the second of the three arteries that supply the gastrointestinal tract:
The superior mesenteric artery supplies circulation for almost the entire small intestine
beginning at the second portion of the duodenum
This artery is crucial to the function of the human digestive system. Stenosis (narrowing) of this artery decreases blood flow to the small intestine, and can cause abdominal angina. Blockage of the artery causes mesenteric ischemia or necrosis and will result in death unless surgically treated or otherwise reversed immediately.
This artery also is involved in superior mesenteric artery syndrome, a form of intestinal obstruction.