The superior mesenteric vein, also known as (SMV) transports blood from the small intestine and the cecum. It follows a path similar to that of the superior mesenteric artery.

This vein is located in the abdominal cavity next to the superior mesenteric artery. Where it ends, near the neck of the pancreas, it forms the hepatic portal vein by coming together with the splenic vein.

Other tributaries of SMV drain other organs such as the stomach, large intestine, and appendix. Some of these include the middle colic vein, right colic vein, veins from the ileum, and veins from the jejunum.

Thrombosis is the only pathologic disorder associated with this vein and it is uncommon. Thrombosis is a blood clot in a blood vessel, which leads to restricted blood flow and circulation throughout the body.

Another rare condition that can be associated with the superior mesenteric vein is mesenteric ischemia. This is when the small intestine is inflamed or possibly injured due to inadequate blood supply, and this can be fatal.