Key Points

• An aneurysm is a balloon-like bulge in an artery. Arteries are blood vessels that carry oxygen-rich blood from your heart to your body.
• Arteries have thick walls to withstand normal blood pressure. However, certain medical problems, genetic conditions, and trauma can damage or injure artery walls. The force of blood pushing against the weakened or injured walls can cause an aneurysm.
• An aneurysm can grow large and burst (rupture) or cause a dissection. Rupture causes dangerous bleeding inside the body. A dissection is a split in one or more layers of the artery wall. The split causes bleeding into and along the layers of the artery wall. Both conditions are often fatal.
• Most aneurysms occur in the aorta—the main artery that carries blood from the heart to the rest of the body. The aorta goes through the chest and abdomen.
• An aneurysm that occurs in the part of the aorta that's in the chest is called a thoracic aortic aneurysm (TAA). An aneurysm that occurs in the part of the aorta in the abdomen is called an abdominal aortic aneurysm (AAA). Aneurysms also can occur in other arteries, but these types of aneurysm are less common.
• A number of factors can damage and weaken the walls of the aorta and cause aortic aneurysms. Examples include aging, smoking, high blood pressure, atherosclerosis, infections, certain genetic conditions, and trauma. Family history also may play a role in causing aortic aneurysms.
• The signs and symptoms of an aortic aneurysm depend on the type of aneurysm, its location, and whether it has ruptured or is affecting other parts of the body. Aneurysms can develop and grow for years without causing signs or symptoms.
• Your doctor may find an aortic aneurysm by chance during a routine physical exam. More often, doctors find aneurysms during tests done for other reasons, such as chest or abdominal pain. To diagnose and evaluate an aneurysm, your doctor may recommend one or more tests.
• Aortic aneurysms are treated with medicines and surgery. A small aneurysm that's found early and isn't causing symptoms may not need treatment. Every aneurysm should be evaluated.
• Your doctor may prescribe medicines before surgery or instead of surgery. He or she may recommend surgery if your aneurysm is growing quickly or if it reaches a size linked with an increased risk of rupture or dissection.
• The best way to prevent an aneurysm is to avoid the factors that put you at higher risk for one. You can't control all of the risk factors for aneurysm, but lifestyle changes can help you reduce your risks. Examples of lifestyle changes include following a healthy diet, doing physical activity, not smoking, and treating other medical conditions such as high blood pressure and high blood cholesterol.
• If you have an aortic aneurysm, it's important to follow your treatment plan and have ongoing medical care. Early diagnosis and treatment help prevent many cases of rupture and dissection.