Vessels that supply blood to the small and large intestines, liver, spleen and stomach are called the mesenteric arteries. Mesenteric ischemia occurs when not enough blood is able to flow through these arteries. Without oxygen from the blood, these organs—primarily the small and large intestines—cannot function normally.
The mesenteric arteries may become blocked by a blood clot or become hardened or obstructed by a build-up of plaque—a sticky substance made largely of cholesterol. If blood flow to the intestines is blocked or restricted, patients may experience extreme abdominal pain. Worse still, if the blockage persists for a longer period of time, intestinal tissue may begin to die. Typically only the small intestines are affected, but other abdominal organs may become involved, including the stomach, liver, and colon.
Beyond plaque and blood clots, the conditions that put patients at risk for mesenteric ischemia include: coagulation disorders, low blood pressure, congestive heart failure, aortic dissections, restriction or blockage of the vessels in the bowel, fibromuscular dysplasia, and arteritis.