Unveiling Aortoenteric Fistula (AEF): Diagnosis and Treatment Solutions

An aortoenteric fistula is a rare but life threatening complication of aortic surgery requiring immediate surgical repair. Early symptoms include abdominal pain or vomiting blood.

A fistula is an abnormal connection between two spaces in your body. An aortoenteric fistula (AEF) is a hole that connects your gastrointestinal (GI) tract with your aorta, the main artery that carries blood away from your heart.

The most common cause of an AEF is complications from aorta surgery. It can also occur as a complication of conditions that cause aortic inflammation.

Without prompt treatment to repair your aorta, an AEF causes massive GI bleeding and is almost always fatal. Emergency surgery can potentially be lifesaving.

Read on to learn about this serious condition, including its causes, symptoms, and treatment options.

What causes an aortoenteric fistula?

An AEF is an abnormal connection between your aorta and your GI tract. Your aorta is the largest blood vessel in your body. It carries blood from your heart to the rest of your body. The duodenum, or the upper part of your small intestines, is the most commonly affected part of your GI tract.

AEFs are extremely rare, occurring in an estimated 1 in 143 million people per year.

An AEF can be primary or secondary. Primary fistulas are less common. They develop due to direct friction and inflammation of your aorta. Underlying causes can include:

• aortic aneurysms, most commonly
• foreign objects in your body
• tumors
• radiation therapy
• infections such as tuberculosis and syphilis

Secondary AEFs develop following surgery of your aorta, typically after receiving a synthetic graft to treat an abdominal aortic aneurysm.

There’s a relatively high risk of developing a fistula after open aortic artery repair compared with endovascular repair. Open repair means that a surgeon treats an aneurysm through a large incision to access your aorta. Endovascular surgery involves using a thin tube doctors insert into your bloodstream.

AEFs are more common in males. Abdominal aortic aneurysms and aortic surgery are also more common in males.

What symptoms does an aortoenteric fistula cause?

AEFs often present with massive and hard-to-control GI bleeding that can lead to shock and death.

Other signs and symptoms include:

• low blood pressure
• sudden and intense abdominal pain
• vomiting blood
• abdominal mass with a pulse

In a 2021 study, GI bleeding was among the initial symptoms in 60% of 57 people treated at one medical center from 1999–2019 for secondary AEFs. Abdominal pain was among the initial symptoms in 56% of people.

WHEN TO CALL 911

GI bleeding is a medical emergency that requires immediate medical attention. It’s critical to see a doctor if you develop symptoms such as:

• vomiting blood
• dark, tarry stools
• bright red blood in your stool

What are the possible complications of aortoenteric fistula?

Potential complications that can occur from the fistula or treatment for the fistula include:

• shock
• multiorgan failure
• heart attack
• arrhythmia
• aortic rupture
• infection
• bowel leakage from your fistula
• sepsis

How do doctors diagnose aortoenteric fistula?

If a doctor suspects AEF, they’ll proceed directly to surgery without further tests. About two-thirds of diagnoses are made in the operating room. Many diagnoses aren’t made until the autopsy report after death.

If you don’t have a history of aortic surgical repair or an aortic aneurysm, a doctor might need to run other tests before suspecting an AEF. Tests may include:

• ultrasound
• upper esophagogastroduodenoscopy (EGD)
• computed tomographic (CT) angiography

How do doctors repair an aortoenteric fistula?

AEFs require immediate surgery to avoid life threatening complications. Doctors can perform surgery through a traditional open procedure or a less-invasive endovascular approach The goals of surgery are to:

• stop the bleeding
• confirm the diagnosis
• repair the damaged part of your aorta

Open repair

During an open repair, a doctor will make a large incision in your abdomen to access your aorta. They’ll then repair the fistula. They may also remove the graft from a previous surgery as well as any dead or infected tissue.

Open surgery is associated with lower rates  of sepsis or postsurgical infection for people in good enough overall health to handle the increased physical demand of the surgery.

Endovascular repair

Doctors perform endovascular surgery by accessing your aorta from within your blood vessel. Your surgeon will make an incision over one of your arteries, often in your groin, and insert a long, thin tube with special tools until it reaches your aorta. They’ll use this tube to repair your fistula.

Endovascular repair is generally the preferred technique for people with primary AEFs  

 without signs of infection. Doctors also often use it to stabilize critically ill people with secondary AEFs or those not in good enough health to undergo open surgery.

What is the outlook for people after aortoenteric fistula repair?

An AEF repair is a potentially lifesaving procedure. Without surgery, the mortality rate of someone with an AEF is essentially 100% In a 2021 study, researchers reported the following mortality rates among 57 people who received surgery to treat secondary AEFs:

Timeframe	Mortality rate
30 days	35%
90 days	39%
180 days	42%

The researchers also found that 70% of people developed complications, with GI complications being the most common.

Frequently asked questions

Here are some frequently asked questions people have about AEFs.

What is the mortality rate for aortoenteric fistula?

Without treatment, people with AEFs have a mortality rate of effectively 100%  Many people die before they receive a diagnosis. In a 2021 study, the 30-day mortality rate among people who received surgical repair for secondary AEFs was 35%.

Is aortoenteric fistula painful?

Abdominal pain is one of the most common symptoms of AEF. More than half of people with AEF report it as one of the initial symptoms. Pain may come on suddenly and be intense.

How long is recovery after aortoenteric fistula repair?

It can take weeks to months to recover fully from aortic surgery. It often takes 6–12 weeks to be able to return to work following open abdominal aortic aneurysm repair.

Q: What is an aortoenteric fistula (AEF)?

A: An aortoenteric fistula is an abnormal connection between the aorta (the main artery carrying blood from the heart) and the gastrointestinal tract.

Q: What causes an AEF?

A: The most common cause is a complication from previous aortic surgery. Other potential causes include aortic aneurysms, tumors, radiation therapy, and infections like tuberculosis.

Q: What are the symptoms of an AEF?

A: Symptoms include massive gastrointestinal bleeding, vomiting blood, sudden severe abdominal pain, and low blood pressure. Gastrointestinal bleeding is often the initial symptom.

Q: What complications can an AEF cause?

A: Potential complications include shock, multi-organ failure, heart attack, aortic rupture, infection, sepsis, and death if not treated promptly.

Q: How is an AEF diagnosed?

A: About two-thirds of cases are diagnosed during emergency surgery. Tests like CT angiography or endoscopy may be done if no prior aortic surgery history.

Q: How is an AEF treated?

A: Emergency surgery is required to repair the fistula and stop bleeding, either through an open abdominal procedure or an endovascular approach threading tools through the arteries.

Q: What is the outlook after AEF repair surgery?

A: Without treatment, AEFs are almost always fatal. With surgery, the 30-day mortality rate is around 35%, and complications are very common, but repair can be lifesaving.

Takeaway

An AEF is a medical emergency where your aorta becomes connected with your GI tract. It can cause life threatening GI bleeding that requires immediate surgical repair.

AEFs are extremely rare and usually occur as a complication of aortic surgery. It’s essential to get immediate medical attention any time you develop symptoms of GI bleeding, such as vomiting blood or finding blood in your stools.