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Acute Mesenteric Ischemia


Parswa Ansari

, MD, Hofstra Northwell-Lenox Hill Hospital, New York

Reviewed/Revised Apr 2023

Acute mesenteric ischemia is sudden blockage of blood flow to part of the intestines, which may lead to gangrene and perforation (puncture).

  • Severe abdominal pain develops suddenly.

  • The diagnosis may be made by angiography.

  • Immediate treatment is needed using angioplasty or surgery.

Acute mesenteric ischemia has multiple causes. The most common are

  • Arterial embolism

  • Arterial thrombus

Arterial embolism is a blood clot or piece of atherosclerotic plaque material (the buildup of cholesterol and other fatty materials in an artery) that travels from its origin in the heart or aorta to lodge in the smaller arteries (in this case those of the intestines).

Arterial thrombus is a blood clot that forms spontaneously in the arteries or veins, including those of the intestines, blocking flow.

Blockage of blood flow for more than 6 hours can cause the affected area of intestine to die, allowing intestinal bacteria to invade the person's system. Shock, organ failure, and death are likely if intestinal death occurs.

Symptoms of Acute Mesenteric Ischemia

At first, the person has severe abdominal pain Acute Abdominal Pain Abdominal pain is common and often minor. Severe abdominal pain that comes on quickly, however, almost always indicates a significant problem. The pain may be the only sign of the need for surgery... read more that usually develops suddenly. However, the person usually has only mild pain when the doctor presses on the abdomen during the examination (unlike in disorders such as appendicitis or diverticulitis, in which pressing makes the pain much worse).

Later, as the intestine starts to die, the doctor's examination of the abdomen causes more severe pain.

Diagnosis of Acute Mesenteric Ischemia

  • A doctor's examination

  • Angiography

If the person has typical symptoms of acute mesenteric ischemia or if the abdomen is very tender, doctors usually take the person right to surgery.

If the diagnosis of acute mesenteric ischemia is not clear, doctors do CT angiography CT angiography Computed tomography (CT) is a type of medical imaging that combines a series of x-rays to create cross-sectional, detailed images of internal structures. In computed tomography (CT), which used... read more CT angiography or mesenteric angiography to look for blockages in the arteries that supply blood to the intestines. In CT angiography, CT (computed tomography) and a radiopaque dye that is injected in an arm vein are used to produce images of blood vessels. In mesenteric angiography, a small flexible tube (catheter) is threaded through the artery in the groin and into the arteries of the intestines. A radiopaque dye is injected through the catheter to make the arteries easier to see on x-rays that are taken at the same time. Magnetic resonance angiography Magnetic resonance angiography (MRA) Magnetic resonance imaging (MRI) is a type of medical imaging that uses a strong magnetic field and very high frequency radio waves to produce highly detailed images. During an MRI, a computer... read more Magnetic resonance angiography (MRA) is another kind of angiography that may be done to provide detailed images of blood vessels.

Treatment of Acute Mesenteric Ischemia

  • Surgery

  • Angioplasty and placement of a stent

  • Medications to prevent clotting

If mesenteric ischemia is diagnosed during surgery, the blood vessel blockage can sometimes be removed or bypassed, but other times the affected intestine must be removed.

If mesenteric ischemia is diagnosed during CT angiography or mesenteric angiography, doctors may try to relieve the blockage in the blood vessels using angioplasty and placement of a stent. In angioplasty, a small flexible tube (catheter) is threaded through the artery in the groin and into the arteries of the intestines, and angiography is done. If a blockage is seen, sometimes it can be opened by injecting certain medications, suctioning out a blood clot using a special angiography catheter, or inflating a small balloon within the artery to widen it and then placing a small tube or manufactured mesh (a stent) to keep it open. If doctors cannot successfully open the blockage using these procedures, the person needs surgery to open the blockage or to remove the affected portion of the intestine.

After recovery, many people need to take a medication to help prevent blood clotting.

Prognosis for Acute Mesenteric Ischemia

If the doctor can make the diagnosis and begin treatment early, people usually recover well.

If the diagnosis is not made or if treatment is not started until some of the affected intestine has died, 70 to 90% of people die. A person cannot survive if almost all the small intestine dies or is removed.

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