Mesenteric artery ischemia is a narrowing or blockage of one or more of the three mesenteric arteries, which are the major arteries supplying the small and large intestines.

Narrowing of the arteries that supply blood to the intestine causes mesenteric ischemia. The arteries that supply blood to this area run directly from the aorta, the main artery from the heart.

Mesenteric artery ischemia is often seen in people with hardening of the arteries elsewhere in the body (for example, with coronary artery disease or peripheral vascular disease). The condition is more common in smokers and in patients with high cholesterol.

Mesenteric ischemia may also be caused by a blood clot (embolus) that moves through the blood and suddenly blocks one of the mesenteric arteries. The clots usually come from the heart or the aorta. These clots are more commonly seen in patients with abnormal heart rhythms (arrhythmias), such as atrial fibrillation.

Symptoms of long-term (chronic) mesenteric artery ischemia caused by atherosclerosis:

• Abdominal pain after eating
• Diarrhea

Symptoms of sudden (acute) mesenteric artery ischemia due to a traveling blood clot:

• Diarrhea
• Sudden severe abdominal pain
• Vomiting

In acute mesenteric ischemia, blood tests may show a higher-than-normal white blood cell (WBC) count and changes in the blood-acid level.

A CT scan may show problems with the blood vessels and the intestine.

A mesenteric angiogram is a test that involves injecting a special dye into your bloodstream to highlight the arteries of an intestine. Then x-rays are taken of the area. This can show the location of the blockage in the artery.

Acute mesenteric artery ischemia is an emergency. Surgery is performed to remove the clot. In some cases, the surgeon must also create a bypass around blockage.

Surgery for chronic mesenteric artery ischemia involves removing the blockage and reconnecting the arteries to the aorta. A bypass around the blockage is another procedure. It is usually done with a plastic tube graft.

An alternative to surgery is a stent. It may be inserted to enlarge the blockage of the mesenteric artery or deliver medicine directly to the affected area. This is a rather new technique and should only be done by experienced health care providers.

In the case of chronic mesenteric ischemia, the outlook after a successful surgery is good. However, if appropriate lifestyle changes (such as a healthy diet and exercise) are not made, any problems with hardening of the arteries will generally get worse over time.

Persons with acute mesenteric ischemia usually do poorly, since death of the intestine often occurs before surgery is done. However, when diagnosed and treated right away, patients with acute mesenteric ischemia can be treated successfully.

Tissue death from lack of blood flow (infarction) in the intestines is the most serious complication of mesenteric artery ischemia.

Call your health care provider if you have:

• Changes in bowel habits
• Fever
• Nausea
• Severe abdominal pain
• Vomiting

Prevention includes following lifestyle changes that reduce your risk for atherosclerotic disease. This includes:

• Exercise
• Follow a healthy diet
• Keep your blood pressure under control
• Stop smoking

To prevent acute mesenteric artery ischemia, also control any heart rhythm problems.

Belkin M, Owens CD, Whittemore AD, Donaldson MC, Conte MS, Gravereaux E. Peripheral Arterial Occlusive Disease. In: Townsend CM Jr., Beauchamp RD, Evers BM, Mattox KL. Townsend: Sabiston Textbook of Surgery. 18th ed. Philadelphia, Pa: Saunders Elsevier; 2008: chap 66.