Abdominal Aortic Aneurysms (AAA)

Good morning, everyone! Welcome back for another day of 2026’s #AorticDiseaseAwarenessMonth!

Yesterday, we discussed thoracic aortic aneurysms (TAAs). Today, we’re moving farther down the aorta to talk about abdominal aortic aneurysms, or AAAs.

What is an aneurysm?

To review, an aneurysm is an abnormal enlargement or bulging of a weakened area of a blood vessel. As an aneurysm grows, the wall of the vessel can become increasingly vulnerable to serious complications, including rupture.

What is an abdominal aortic aneurysm?

An abdominal aortic aneurysm is an enlargement of the portion of the aorta that travels through the abdomen. An AAA is generally defined as an abdominal aorta measuring 3.0 cm or greater in diameter.

Most AAAs develop slowly, but as they enlarge, the risk of rupture increases. A ruptured AAA can cause life-threatening internal bleeding and requires immediate medical attention.

Below is a representative diagram showing an abdominal aortic aneurysm below the kidneys.

What are the symptoms of an AAA?

One of the challenges with AAAs is that most cause no symptoms, which is why screening is so important for people at increased risk.

When symptoms do occur, they may include:

• A deep or persistent pain in the abdomen or side

• Persistent back pain

• A pulsating sensation near the belly button

  
  

A ruptured AAA may cause sudden, severe abdominal or back pain, weakness, dizziness, fainting, or other signs of internal bleeding. A suspected rupture is a medical emergency and requires immediate care.

What causes an AAA, and who is at risk?

Several factors are associated with the development of AAA. Some of the most important include:

• Increasing age

• Smoking or a history of smoking

• Male sex

• Family history of AAA

• High blood pressure

• High cholesterol and atherosclerotic cardiovascular disease

  
  

Smoking is an especially important modifiable risk factor for the development, growth, and rupture of AAA.

Screening and Diagnosis

Because most AAAs do not cause symptoms, they are often discovered through screening or incidentally during imaging performed for another reason.

Abdominal ultrasound is the standard screening test. It is quick, noninvasive, and does not use radiation, allowing clinicians to estimate and measure the diameter of the abdominal aorta.

In the United States, one-time ultrasound screening is recommended for men ages 65–75 who have ever smoked. Screening may also be considered for certain other individuals based on factors such as age, smoking history, sex, and family history.

Management and Treatment

Not every AAA requires surgery. Smaller aneurysms are generally monitored with periodic imaging, with the frequency of surveillance depending on the aneurysm's size and other individual factors.

Management also focuses on cardiovascular health and modifiable risk factors, including stopping smoking and controlling blood pressure and cholesterol.

As an aneurysm becomes larger, grows rapidly, or causes symptoms, repair may be recommended. For many patients, repair is considered around 5.5 cm in men and 5.0 cm in women, although the decision is individualized based on anatomy, symptoms, growth, overall health, and other risk factors.

AAA repair may be performed through open surgery or with a less invasive approach called endovascular aneurysm repair (EVAR).

A ruptured AAA is a life-threatening emergency requiring immediate treatment.

Know Your Risk

If you have a history of smoking, a family history of abdominal aortic aneurysm, or other risk factors for aortic disease, talk with your healthcare provider about whether AAA screening may be appropriate for you.

That wraps up today’s Aorta Ed! #AorticDiseaseAwarenessMonth

Zach