Chronic intestinal ischemia, in which blood flow to the intestines is reduced over time, is characterized by:
Chronic intestinal ischemia may progress to an acute episode. If this happens, you might experience severe abdominal pain after weeks or months of bouts of pain after eating.
Causes
The aorta is the large artery that supplies your body's vessels with oxygen-rich blood pumped by your heart. The portion of the aorta extending below your heart into your abdomen is the abdominal aorta. Three arteries branching off the abdominal aorta supply almost all of the blood to your digestive tract. These arteries are the:
When the flow of blood through these arteries or their adjacent draining veins is altered, whether the change is acute or chronic, intestinal ischemia results.
Like other arteries in your body, any or all of the arteries that serve your digestive tract may be affected by an accumulation of cholesterol particles, scar tissue, calcium and other cellular debris (atherosclerosis), which narrows those arteries and restricts the amount of blood moving through them. Atherosclerotic buildup can progressively reduce blood flow to your small intestine, your large intestine or both. Chronic intestinal ischemia is often the result of atherosclerotic buildup.
Most of the time, acute intestinal ischemia is due to a blood clot that forms in your heart and then travels to one of your intestinal arteries. Other times a blood clot may develop in a vein leading away from the intestines, diminishing the outflow of deoxygenated blood. Sometimes intestinal ischemia occurs because a portion of your intestine becomes trapped due to a hernia (strangulated hernia) or due to adhesions from a previous abdominal surgery. Other times it occurs because of heart failure or low blood pressure.
Whatever the cause, diminished blood flow within your digestive tract leaves cells with insufficient oxygen. Under these conditions, cells become weak and die. As more and more cells are damaged, inflammation and ulcers develop. This leads to an inability to absorb food and nutrients, resulting in bloody diarrhea. If damage is severe enough, infection and gangrene may result. If untreated for long, intestinal ischemia can be fatal.
Intestinal ischemia is often divided into several categories:
Colon ischemia (ischemic colitis)
Disrupted blood flow to the colon is the most common type of intestinal ischemia. It most often occurs in older adults, although it may develop in younger people.
Signs and symptoms of colon ischemia are generally milder than with other forms of intestinal ischemia, and severe complications are uncommon. For most people, colon ischemia appears as a sudden onset of mild, crampy pain on the left side of the abdomen. What causes diminished blood flow to the colon isn't always clear, but a number of conditions can make you more vulnerable to colon ischemia:
Acute mesenteric ischemia
This type of intestinal ischemia usually affects the small intestine. It has an abrupt onset and may be due to:
Chronic mesenteric ischemia
Chronic mesenteric ischemia, also known as intestinal angina, results from atherosclerosis. The disease process is generally so gradual that at least two of the three major arteries supplying your intestines become severely narrowed or completely obstructed before you experience symptoms. A potentially dangerous complication of chronic mesenteric ischemia is the development of a blood clot within a diseased artery, causing acute mesenteric ischemia.
Ischemia due to mesenteric venous thrombosis
Occasionally, a blood clot will develop in a vein draining deoxygenated blood away from your intestines. Blockage of the vein causes intestinal congestion, swelling and bleeding. A blood clot in a mesenteric vein may result from:
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The arteries that supply almost all of the blood needed by your digestive tract are the celiac, the superior mesenteric and the inferior mesenteric arteries. Any or all of these arteries may be ...
Risk factors
Many of the risk factors for intestinal ischemia are those associated with atherosclerosis and clogging of the mesenteric arteries. These factors include:
Your risk is also higher if you have a history of atherosclerosis that affects blood flow in other areas of your body, such as your heart (coronary artery disease), legs (peripheral vascular disease) or the arteries serving your brain (cerebrovascular disease).
Other factors that can increase your risk of intestinal ischemia include low blood pressure, congestive heart failure, an irregular heartbeat, a blood clotting disorder, a hernia and previous abdominal surgery.
Risk factors for ischemia due to mesenteric venous thrombosis include extended bed rest, obesity, certain types of cancer, birth control pills, smoking, and a history of high blood pressure or heart disease.
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When to seek medical advice
Seek immediate medical care anytime you have sudden, persistent abdominal pain. A delay in treatment may make successful treatment more difficult. Also, see your doctor promptly if you have blood in your stool or if you have chronic abdominal pain after eating, especially if you're also losing weight unexpectedly.
Screening and diagnosis
If your doctor suspects intestinal ischemia, he or she may want to conduct a thorough medical evaluation because signs and symptoms of intestinal ischemia can be similar to those of other disorders, such as ulcers, as well as stomach, pancreatic or colon cancer.
You may undergo several diagnostic tests, based on your signs and symptoms, including:
Arriving at a diagnosis
In general, the diagnoses of various types of intestinal ischemia are as follows:
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Coronary angiography and other heart catheterization procedures![]() |
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MRI: Viewing the body's hidden structure![]() |
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Complications
Sometimes blood flow to your digestive tract is completely and suddenly cut off due to a blood clot that travels to the area, often from your heart. The same is true if a clot develops in one of the three arteries that serve your digestive tract where there's already some atherosclerotic buildup. It's also possible that blood clots or atherosclerotic buildup may be dislodged from a larger artery or the aorta by a catheter during a diagnostic procedure, which can cause a blockage of smaller arteries downstream. These are medical emergencies.
Blockage of the blood flow to your intestine may result in death of intestinal tissue (infarction or necrosis). If this life-threatening situation occurs, you'll need surgery to clear the blockage and to remove the portion of the intestine that has died. In order to limit the amount of intestinal tissue removed, your surgeon may plan to operate again (second-look operation) to be sure that remaining bowel tissue is healthy.
After removing damaged intestinal tissue, your surgeon may be able to connect the healthy ends together. If that's not possible, your surgeon may need to perform a procedure called an ostomy. In this procedure, the surgeon creates an opening in your abdomen to pull a section of your intestine to the surface. A bag is then attached to this opening, and your waste is expelled into the bag.
Blockage of blood flow to the colon can lead to scarring and narrowing of your colon, which may require surgical treatment.
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Ostomy: Adapting to life after colostomy, ileostomy or urostomy![]() |
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Treatment
Treatment of intestinal ischemia involves restoring a sufficient blood supply to your digestive tract. Options vary depending on the cause and severity of your condition:
Colon ischemia. Antibiotics are often used to treat or prevent infections. Your doctors also will treat any underlying medical condition, such as congestive heart failure or an irregular heartbeat. You'll need to stop any medications that constrict your blood vessels, such as migraine drugs, hormone medications and some heart drugs.
If your colon has been damaged, you may need surgery to remove the dead (infarcted) tissue. Or, you may need surgery to bypass a blockage in one of your intestinal arteries. The procedure is similar to what's done when blocked coronary arteries of the heart are bypassed to redirect blood flow around a blockage. Because colon cancer is one of the causes of colonic ischemia, your doctor will likely consider a full colonoscopy after your symptoms improve to get a better look at your colon.
Acute mesenteric artery ischemia. Surgery is often necessary to remove a blood clot, bypass an artery blockage, or to repair or remove a damaged section of intestine. Treatment also may include medications to prevent clots from forming, dissolve clots or dilate blood vessels.
If angiography is done to diagnose the problem, the radiologist may simultaneously be able to remove a blood clot, or open up the narrowed artery with angioplasty. Angioplasty involves using a balloon inflated at the end of a catheter to compress the fatty deposits and stretch the artery, making a wider path for the blood to flow. A spring-like metallic coil (stent) may also be placed in your artery to help keep it open.
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Prevention
Intestinal ischemia is often a warning sign of more widespread atherosclerosis. If you have health conditions such as diabetes, high blood pressure, or elevated blood cholesterol or triglycerides, any of which could result in or aggravate atherosclerosis, work closely with your doctor to manage and control these conditions.
The preventive steps that you and your doctor discuss may include:
Taking steps to prevent atherosclerosis will reduce your risk of intestinal ischemia as well as other serious disorders, such as heart attack and stroke.
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