Median arcuate ligament syndrome (MALS) refers to abdominal pain resulting from a ligament pushing on the artery and nerves connected to the digestive organs in the top part of your abdomen, like the stomach and liver.
Other names for the condition are Dunbar syndrome, celiac artery compression syndrome, celiac axis syndrome, and celiac trunk compression syndrome.
When accurately diagnosed, surgical treatment usually results in a good outcome for this condition.
MALS is a rare condition involving a fibrous band called the median arcuate ligament. With MALS, the ligament presses tightly against the celiac artery and the nerves around it, narrowing the artery and reducing blood flow through it.
The celiac artery transports blood from your aorta (the large artery coming from your heart) to your stomach, liver, and other organs in your abdomen. When this artery is compressed, the amount of blood flowing through it goes down, and these organs don’t get enough blood.
Without enough blood, the organs in your abdomen don’t get enough oxygen. As a result, you feel pain in your abdomen, which is sometimes called intestinal angina.
The condition occurs most often in thin women who are between 20 and 40 years old. It’s a chronic and recurrent condition.
Doctors aren’t sure what exactly causes MALS. They used to think the only cause was insufficient blood flow to abdominal organs due to the median arcuate ligament narrowing the celiac artery. Now they think other factors, like compression of nerves in the same area, also contribute to the condition.
The hallmark symptoms that characterize the condition are abdominal pain after eating, nausea, and vomiting that usually lead to weight loss.
According to the National Center for Advancing Translational Sciences, abdominal pain occurs in about 80 percent of people with MALS, and a little less than 50 percent lose weight. The amount of weight loss is usually over 20 pounds.
The median arcuate ligament is attached to your diaphragm and passes in front of your aorta where the celiac artery leaves it. Your diaphragm moves when you breath. The movement during exhalation tightens the ligament, which explains why the symptoms mainly occur when a person exhales.
Other symptoms may include:
The abdominal pain can travel, or radiate, to your back or flank.
People with MALS may avoid or be afraid to eat because of the pain they feel after they do.
The presence of other conditions that can cause abdominal pain must to be excluded before a doctor can make a diagnosis of MALS. These conditions include an ulcer, appendicitis, and gallbladder disease.
Doctors can use several different tests to look for MALS. Sometimes more than one test is needed. Possible tests include:
- Angiography. A catheter is inserted into the artery and dye is injected. This allows the technician performing the test to see if the artery gets smaller during exhalation and bigger during inhalation on X-rays that show movement.
- MRI angiogram. Dye is injected through a vein and an MRI scan done to get a look at the celiac artery.
- CT angiogram. Dye is injected through a vein and a CT scan performed to create images of the celiac artery.
If your doctor suspects you have MALS, they can confirm this diagnosis with Doppler ultrasound, which shows the volume and speed of blood moving through an artery.
MALS is a chronic condition, so it won’t go away on its own.
MALS is treated by cutting the median arcuate ligament so that it can’t compress the celiac artery and surrounding nerves anymore. This can be done through a laparoscopic procedure, using surgical instruments inserted through several small incisions in the skin, or through open surgery.
Often that’s the only treatment needed. But if symptoms don’t go away, your doctor may recommend another procedure to either place a stent to keep the artery open or insert a graft to bypass the narrow area of the celiac artery.
After laparoscopic surgery, you’ll likely stay in the hospital for three or four days. Recovery from open surgery often takes a little longer because the surgical wound has to heal enough so it doesn’t reopen, and it takes your intestines longer to function normally again.
After surgery, your doctors will first get you up and walking around your room and then the hallways. You may receive physical therapy to help with this.
Observation and pain management
Your doctor will be sure your digestive tract is functioning normally before you can start to eat anything, and then your diet will be increased as tolerated. Your pain will be managed until it’s well-controlled. When you can get around without difficulty, you’ve returned to a normal diet, and your pain is controlled, you’ll be discharged from the hospital.
Once you’re home, your strength and stamina can gradually return over time. It may take at least three to four weeks before you’re back to your usual activity and routine.
The symptoms of MALS can be bothersome and may lead to significant weight loss. Because it’s rare, MALS is difficult to diagnose, but the condition can be surgically treated. Although a second surgery is sometimes needed, you can expect a complete recovery.