Mesenteric Ischemia

Mesenteric ischemia is a life-threatening condition that happens when parts of your digestive system don’t get enough blood flow. This usually occurs because of a blockage in blood vessels that supply those areas. It can be acute (sudden) or chronic (long-term).

Without enough blood flow, the affected organs and tissues don’t have enough oxygen and can’t work right. If the blockage is severe enough, the affected organs and tissues may start to die. This condition is often fatal, making rapid diagnosis and treatment important.

The mesentery is an organ in your abdomen (belly) that holds your small and large intestines and other organs in place. A network of blood vessels in the mesentery supplies the organs inside.

Mesenteric ischemia isn’t common. The estimated number of cases is 1 in every 1,000 hospital stays for belly pain. This condition is more common in people over 70, especially those with heart disease or blood clotting disorders.

Types of this condition

Types of mesenteric ischemia include:

• Acute mesenteric ischemia: Usually, a blood clot blocks a critical artery. This can cause sudden and severe symptoms. This is a medical emergency. A subtype of the acute form involves blood vessel tightening, but no clot. This is called non-occlusive mesenteric ischemia (NOMI).
• Chronic mesenteric ischemia: Your mesenteric arteries start to narrow gradually. This condition takes days or weeks to develop, and the symptoms usually worsen over time.

Symptoms of mesenteric ischemia

Symptoms of acute mesenteric ischemia happen suddenly. With chronic mesenteric ischemia, they can happen slowly and usually worsen over six months or more. Some people don’t have symptoms.

It’s very common for the acute type to happen after you have chronic mesenteric ischemia symptoms. Early symptoms from narrow blood vessels suddenly become severe when a new blood clot blocks the narrowed vessels.

Belly pain is the most common symptom. It usually occurs for up to four hours after eating.

Other symptoms may include:

• Nausea and vomiting
• Constipation
• Diarrhea
• Food fear and weight loss
• Fever

Mesenteric ischemia causes

The different types of mesenteric ischemia have different causes:

• Acute mesenteric ischemia: A waxy substance (plaque) can build up inside your arteries. If plaque breaks open, blood clots can form there or get stuck there after coming from elsewhere. A clot can also form in a nearby blood vessel. A tear or bulge in the aorta is another cause.
• Non-occlusive mesenteric ischemia (NOMI): This happens without a blockage. Acute NOMI happens when blood vessels constrict or spasm. This can occur because of certain medications, procedures or conditions (like shock).
• Chronic mesenteric ischemia: This often happens because of diseases that make blood vessels narrower. Examples include atherosclerosis or blood clots. Blood flow to your mesentery drops over time.

Risk factors

Mesenteric ischemia is more common in females and as you age. It usually happens along with heart and blood flow conditions, especially ones that can cause blood clots.

Risk factors for mesenteric ischemia include:

• Atrial fibrillation (an abnormal heart rhythm)
• Coronary artery disease
• Diabetes
• Heart failure
• High blood pressure
• High cholesterol
• Disorders that make your blood clot too easily
• Recent surgery
• Peripheral vascular diseases, like peripheral artery disease
• Tobacco use (past or present)

How to lower your risk

You can do several things to reduce your risk of mesenteric ischemia:

• Get an annual checkup.
• Avoid using tobacco products.
• Take your medications.
• Eat healthy foods.
• Maintain a weight that’s healthy for you.
• Stay active.
• Manage conditions that make blood clots more likely to form.
• Manage and maintain your cholesterol levels.

Complications of this condition

When your intestines start to die from lack of oxygen, bacteria in them can spread to places they don’t belong. This can cause dangerous infections that lead to sepsis, a life-threatening condition.

Other complications depend on whether the condition is acute or chronic:

• Acute type: Damage to your small bowel, weight loss, tearing or rupture of your intestine or colon
• Chronic type: Bowel ischemia, weight loss, malnutrition, progression to acute type

How doctors diagnose this condition

Your healthcare provider diagnoses mesenteric ischemia based on a physical exam, lab tests and imaging that checks blood flow.

This condition is usually hard to diagnose in its early stages because it shares symptoms with common illnesses.

Tests can help diagnose this condition, including:

• Lab tests: Tests can check the amount of oxygen in your blood and how well your blood clots. Tests can also look for signs of infection or tissue damage.
• Ultrasound: Sound waves from a device held against the skin of your belly create an image. If providers get a good image, they can use it to find areas with low or no blood flow.
• CT angiogram: This test is the best way to diagnose mesenteric ischemia. It shows partly or fully blocked vessels.
• Digital subtraction angiogram: This can help when noninvasive tests aren’t enough for a clear diagnosis. A computer removes bones and other structures from the image.
• Endoscopy: Your provider inserts an endoscope into your digestive tract to look for signs of ischemia. They can put the device down your throat or into your rectum to look inside.

How is it treated?

Healthcare providers can treat and reverse mesenteric ischemia when they catch it early enough. The condition becomes more dangerous over time.

The first goal is always to restore blood flow as quickly as possible. The next goal is to remove damaged or dead tissue from your intestine or colon. This is the only way to fix the damage and prevent life-threatening complications.

The likely treatments and procedures vary depending on the type of mesenteric ischemia and the location of its cause.

Acute and chronic mesenteric ischemia

Treatment for the acute or chronic type includes:

• Surgery to remove blood clots
• Angioplasty to widen narrow blood vessels and place a stent to keep a blood vessel open
• Bypass surgery using a section of blood vessel from another place in your body to reroute blood
• Surgery to remove dead or damaged tissue and repair the area around it
• Medications like “clot-busters” (thrombolytics), antibiotics and blood thinners

Non-occlusive mesenteric ischemia

Because NOMI usually involves blood vessels that constrict, providers treat what causes that.

Treatment may include:

• Stopping prescription medications that make blood vessels tighten
• Treating an illness to improve blood flow to the mesentery
• Performing an angioplasty to widen the affected blood vessel
• Giving vasodilators to make your blood vessels expand

When should I see my healthcare provider?

Seek immediate medical care if you have severe belly pain or other symptoms of acute mesenteric ischemia. You should also seek care if chronic symptoms suddenly change or get worse.

If you have chronic mesenteric ischemia, care for it as your provider instructs. Follow-up visits with your provider are important to avoid long-term problems and reduce your risk of complications.

What can I expect if I have this condition?

Most people will start to feel better when blood flow to the affected area improves. Others will likely start to feel better within days or weeks. Recovery from surgery takes longer, but an operation can give you years of relief.

When treatment doesn’t happen quickly, acute mesenteric ischemia is often fatal. Between 6 and 8 out of 10 people die from the acute type of this condition. But these odds improve when treatment happens quickly.

Without treatment for the chronic type, nearly 10 out of 10 people don’t survive five years. Acute NOMI usually takes longer to become severe but is still dangerous. It’s fatal in many cases.

People with mesenteric ischemia also have a much higher risk of other ischemia-related conditions. These include heart attack, stroke and pulmonary embolism. You may need to take blood thinners for the rest of your life.

Over time, a widened artery can get narrow again. You may need more treatment if this happens.