What causes an aortic aneurysm?

Mark J. Russo, MD

Thoracic Surgery (Cardiothoracic Vascular)

Thoracic aortic aneurysms may be caused by different disease processes, especially in respect to their location. Examples of different locations of thoracic aortic aneurysms and their causes may include, but are not limited to, the following:

Ascending Thoracic Aneurysm

cystic medial degeneration (necrosis): breaking down of the tissue of the aortic wall. This is the most common cause of this type of thoracic aortic aneurysm.
genetic disorders which affect the connective tissue, such as Marfan's syndrome and Ehlers-Danlos syndrome
family history of thoracic aortic aneurysm with no incidence of Marfan's syndrome
atherosclerosis: hardening of the arteries caused by a build-up of plaque in the inner lining of an artery. This is a rare cause of ascending thoracic aortic aneurysm.
infection, syphilis (rare causes of thoracic aortic aneurysm)

Aortic Arch Thoracic Aneurysm

Takayasu's arteritis: a type of vasculitis that causes inflammation of the arteries
atherosclerosis
continuation of an ascending and/or descending aortic aneurysm

Descending Thoracic and Abdominal Aortic Aneurysm - Atherosclerosis is most often associated with descending aneurysms and is thought to play an important role in aneurysmal disease. The following risk factors associated with atherosclerosis such as:

age (greater than 55)
male gender
family history (first-degree relatives such as father or brother)
genetic factors
hyperlipidemia (elevated fats in the blood)
hypertension (high blood pressure)
smoking
diabetes

Intermountain Healthcare

The most common causes of aortic aneurysm are atherosclerosis and high blood pressure. At highest risk are males over the age of 60 who smoke and people with a family history of abdominal aortic aneurysm. If you're at risk, you should be evaluated early and monitored regularly.

William J. Quinones Baldrich, MD on behalf of UCLA Health

Vascular Surgery

It is not known what causes aneurysms. Although most aortic aneurysms are associated with atherosclerosis, they are actually degenerative in nature. Degradation of the proteins within the wall of the aorta leads to weakening of the artery, dilation of the segment and formation of the aneurysm. Other causes of aneurysms may include genetic defect, infection or disruption of a previously placed aortic graft with a small bleed covering what is called a false aneurysm. Aortic aneurysms are not associated with brain aneurysms.

CTSurgeryPatients.org

The exact cause of an aortic aneurysm is often difficult to determine, but many factors potentially can contribute to the development of an aortic aneurysm. Some of the most common conditions associated with aneurysm formation are:

congenital or genetic causes for weakness of the artery wall (present from birth)
changes in the aorta due to advanced age
connective tissue disorders such as Marfan or Ehlers-Danlos syndrome
inflammation of the aorta
hardening of the arteries (atherosclerosis) where fat, cholesterol, and other substances (plaque) clog the arteries
injury from falls or motor vehicle accidents
untreated infection such as syphilis or salmonella

In some cases, aneurysms run in families and are classified as “familial," so several members of extended families may be affected by aneurysms in different locations.

This content originally appeared online in "The Patient Guide to Heart, Lung, and Esophageal Surgery" from the Society of Thoracic Surgery.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.

Aneurysms

Aneurysms form balloons in weakened arteries of our bodies, potentially causing life-threatening problems such as a stroke. Although aneurysms can form in any weakened artery, they commonly occur in the arteries of the brain and in the aorta, the central artery that extends from your heart through the center of your abdomen and chest. Certain medical conditions, such as high blood pressure, can weaken the arteries, which deliver oxygenated blood from our heart to the rest of our bodies. The pressure of blood traveling through the arteries can lead to this balloon-like bulge. You can have an aneurysm for years without symptoms or problems. Others can have an aneurysm that pops, which can lead to a stroke if bleeding occurs in the brain. Ruptured aneurysms must be treated quickly, usually within minutes, or it can become deadly: about 50% of all ruptured aneurysms are fatal.

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