The aorta is the large artery that leaves the heart and carries blood through the chest and the abdomen. An aneurysm is a stretched, weakened section of its wall. It may sit in the chest, where it is called a thoracic aneurysm, or in the belly, where it is called an abdominal aortic aneurysm. People are often surprised by the finding. An aneurysm can enlarge for years without pain, and it is frequently noticed on a scan done for another reason.
Often there is nothing to feel
The American Heart Association describes an aneurysm as a bulge in a weakened artery wall that may cause no symptoms at all. Risk is higher with high blood pressure, high cholesterol, tobacco, older age, and a family history of aneurysm. Some people are born with a condition that weakens the wall. In others the cause is never found. A family history matters, because relatives of someone with an aneurysm may need their own scan.
Symptoms that should not wait
- Sudden, severe, tearing or stabbing pain in the chest, back, abdomen, neck, jaw, or shoulder
- Fainting, sudden breathlessness, nausea, or cold, clammy skin
- Sudden weakness, especially on one side of the body, or confusion
- A new pulsing lump in the abdomen, or new steady pain in the abdomen or back
- New hoarseness, trouble swallowing, or chest and upper-back pain, which can come from an aneurysm in the chest and can also come from other conditions
Sudden severe pain can feel like a heart attack. Treat it as an emergency. Call your local emergency service and do not drive yourself. A rupture, or a tear in the wall called a dissection, is a different situation from a stable aneurysm found on a routine scan.
A stable bulge is a follow-up problem. Sudden severe pain is an emergency.
Watching a smaller aneurysm
If the aneurysm is intact and not causing symptoms, many people are followed with repeat scans rather than repaired at once. The 2022 ACC/AHA aortic guideline asks that the aorta be measured the same way each time, preferably with the same type of scan, so a change in size is real and not a difference in technique. Ultrasound, CT, and MRI are all used. Which one fits depends on where the bulge sits. Blood-pressure medicines reduce strain on the wall. They do not repair a rupture, and they are not expected to return the aorta to a normal diameter. Stopping tobacco, and treating cholesterol, are part of the same plan. How often to scan depends on the diameter, the location, and whether it is growing.
When repair is discussed
Repair is done to reduce the chance of rupture. It is not offered for every widened measurement. For an unruptured abdominal aortic aneurysm, the 2022 guideline recommends repair at 5.5 cm or larger in men and 5.0 cm or larger in women, and also when symptoms are coming from the aneurysm. Growth of 0.5 cm in six months may bring that conversation forward. An aneurysm in the chest is judged separately. For many people, surgery on the aortic root or ascending aorta is indicated at 5.5 cm. At experienced centers, 5.0 cm may be reasonable in selected people, and inherited conditions such as Marfan syndrome often use a lower threshold. Confirmed growth of 0.5 cm in one year, or 0.3 cm a year across two years, can also be a reason to operate on the ascending aorta. A single number on a report starts the decision. It does not finish it.
Open surgery and a stent graft
There are two broad ways to repair the aorta. Open surgery replaces the weakened section through an incision. Endovascular repair places a fabric-covered stent graft inside the aorta through the arteries at the groin. For the abdomen this is called EVAR. For the descending chest aorta it is called TEVAR. When an abdominal aneurysm could be treated either way, and the operative risk is low or moderate, the guideline recommends a shared decision that weighs each approach. The shape of the aorta has to suit the stent graft. Some people, including many with certain inherited aortic conditions, are better served by open repair. After a stent graft, scans continue, because the repair itself has to be checked over time.
Your questions, answered
Absence of pain does not measure the diameter. Many aneurysms stay silent until they are large. Whether it is safe to watch depends on the scan, the location, and how fast the diameter is changing.
