Aneurysms

An aneurysm is a spot where the wall of an artery has weakened and stretched, so the artery bulges outward like a thin spot on a garden hose. The bigger it gets, the thinner the wall becomes. The main danger is that it can burst, called a rupture, which causes severe internal bleeding.

The most common place is the aorta, the main artery that runs from the heart down through the chest and belly. An aneurysm in the belly part is called an abdominal aortic aneurysm (AAA). Aneurysms can also form in the arteries that feed the organs, called visceral aneurysms. The splenic artery, which feeds the spleen, is the most common of these. Others involve the arteries to the kidneys, liver or intestines, or the arteries behind the knee (popliteal aneurysms).

Most aneurysms cause no symptoms at all. They are usually found by chance on an ultrasound or CT scan done for another reason, or on a screening ultrasound. Medicare and many plans cover a one-time AAA screening ultrasound for men aged 65 to 75 who have ever smoked, and for people with a family history.

A tender or painful aneurysm is treated as urgent, even if it has not burst, because pain can mean it is growing fast or starting to leak.

Splenic aneurysms deserve special attention in pregnancy. They are more likely to rupture during pregnancy, especially in the last three months, so women who know they have one and are planning a pregnancy should talk with us first.

An ultrasound is a quick, painless way to measure an abdominal aortic aneurysm, with no radiation. A CT angiogram, a CT scan with contrast dye, shows the exact size and shape of the aneurysm and the arteries around it. It is used to plan repair and to study visceral aneurysms, which are harder to see on ultrasound.

What we see

Most small aneurysms are simply watched with regular scans, called surveillance. The risk of rupture for a small aneurysm is very low, lower than the risk of repairing it. How often you are scanned depends on the size.

These intervals follow common guidelines and may be adjusted to your health, the shape of the aneurysm and how fast it is growing.

The goal of treatment is to stop blood from pressing on the weak wall, so the aneurysm cannot burst. Everyone with an aneurysm benefits from quitting smoking and keeping blood pressure under control. There is no pill that shrinks an aneurysm, but a statin and aspirin are often prescribed to protect the heart.

Whether EVAR is possible depends on the shape of your aorta, especially the length of healthy aorta above the aneurysm and the size of the arteries in your pelvis. After EVAR, regular scans check for an endoleak, a leak of blood back into the aneurysm sac. Read more on our endoleaks page.

Splenic artery aneurysms are usually treated when they reach about 2 cm, grow, cause pain, or are found in a woman who is pregnant or could become pregnant. Some visceral aneurysms, called pseudoaneurysms, form after injury, surgery or pancreatitis. These have a thin wall and are usually treated regardless of size.

When I review a scan of an aneurysm, I look at three things: its size, how fast it has grown since the last scan, and the arteries around it that I would need to protect during a repair. Most people I see with a small aneurysm do not need a procedure, just a plan and a reminder for the next scan. When repair is needed, I walk you through the options side by side, including open surgery, because the right answer depends on your anatomy and your overall health.

Fabio Komlos, MD, interventional radiologist · About Dr. Fabio Komlos

1. 1
   Preparation

   You do not eat for about 6 hours beforehand. An IV is placed and you receive moderate sedation, so you are relaxed and comfortable.

2. 2
   Reaching the aneurysm

   We numb a small spot in the groin or wrist and guide a thin catheter through the arteries to the aneurysm, using X-ray and contrast dye as a map.

3. 3
   Sealing it off

   We place tiny coils or a liquid embolic agent to block flow into the aneurysm, while protecting the blood supply to the organ where possible. A final picture confirms it is sealed.

4. 4
   Recovery

   The catheter is removed and the pinhole is sealed. You rest for a few hours. Some people have mild belly pain or a low fever for a few days, especially after splenic embolization.

After embolization of the splenic artery, part of the spleen may lose its blood supply. This can cause left-sided belly pain, nausea and a low fever for several days, called post-embolization syndrome. It is managed with pain medicine and usually settles within a week. The spleen usually keeps working because it gets blood from other small arteries. A follow-up CT scan checks that the aneurysm stays sealed.