Mesenteric artery ischemia occurs when there is a narrowing or blockage of one or more of the three mesenteric arteries, the major arteries that supply the small and large intestines.
Mesenteric vascular disease; Ischemic colitis
Narrowing of the arteries that supply blood to the intestine causes mesenteric ischemia. The arteries that supply blood to the intestines run directly from the aorta, the main artery from the heart.
Mesenteric artery ischemia is often seen in people who have hardening of the arteries in other parts of the body (for example, those with coronary artery disease or peripheral vascular disease). The condition is more common in smokers and in patients with high blood pressure or blood 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 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 hardening of the arteries (atherosclerosis):
Symptoms of sudden (acute) mesenteric artery ischemia due to a traveling blood clot:
In acute mesenteric ischemia, blood tests may show a higher than normal white blood cell count and changes in the blood acid level. There may be bleeding in the GI tract.
A Doppler ultrasound or 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 the 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. If a blood clot is causing it, you may need to take medicines to dissolve the clot (thrombolytics) and widen the mesenteric arteries (vasodilators). Surgery may be needed to treat mesenteric ischemia. In some cases, the surgeon must also create a bypass around the 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 in the mesenteric artery or deliver medicine directly to the affected area. This is a new technique and it should only be done by experienced health care providers. The outcome is usually better with surgery.
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. Surgery may be needed to remove the dead portion.
Call your health care provider if you have:
The following lifestyle changes can reduce your risk for narrowing of the arteries:
To prevent acute mesenteric artery ischemia, also control any heart rhythm problems that may cause the blood to clot.
Hauser SC. Vascular diseases of the gastrointestinal tract. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 145.