An aneurysm is an abnormal widening or ballooning of a part of an artery due to weakness in the wall of the blood vessel.
It is not clear exactly what causes aneurysms. Some aneurysms are present at birth (congenital). Defects in some parts of the artery wall may be a cause.
Common locations for aneurysms include:
- Major artery from the heart such as the thoracic or abdominal aorta
- Brain (cerebral aneurysm)
- Behind the knee in the leg (popliteal artery aneurysm)
- Intestine (mesenteric artery aneurysm)
- Artery in the spleen (splenic artery aneurysm)
High blood pressure, high cholesterol, and cigarette smoking may raise your risk for certain types of aneurysms. High blood pressure is thought to play a role in abdominal aortic aneurysms. Atherosclerotic disease (cholesterol buildup in arteries) may also lead to the formation of some aneurysms. Certain genes or conditions such as fibromuscular dysplasia can result in aneurysms.
Pregnancy is often linked to the formation and rupture of splenic artery aneurysms.
The symptoms depend on where the aneurysm is located. If the aneurysm occurs near the body's surface, pain and swelling with a throbbing lump is often seen.
Aneurysms in the body or brain often cause no symptoms. Aneurysms in the brain may expand without breaking open (rupturing). The expanded aneurysm may press on nerves and cause double vision, dizziness, or headaches. Some aneurysms may cause ringing in the ears.
If an aneurysm ruptures, pain, low blood pressure, a rapid heart rate, and lightheadedness may occur. When a brain aneurysm ruptures, there is a sudden severe headache that some people say is the "worst headache of my life." The risk of coma or death after a rupture is high.
Treatment depends on the size and location of the aneurysm. Your provider may only recommend regular checkups to see if the aneurysm is growing.
Surgery may be done. The type of surgery that is done and when you need it depend on your symptoms and the size and type of aneurysm.
Surgery may involve a large (open) surgical cut. Sometimes, a procedure called endovascular embolization is done. Coils or stents of metal are inserted into a brain aneurysm to make the aneurysm clot. This reduces the risk for rupture while keeping the artery open. Other brain aneurysms may need to have a clip placed on them to close them off and prevent a rupture.
Aneurysms of the aorta may be reinforced with surgery to strengthen the blood vessel wall.
When to Contact a Medical Professional
Call your provider if you develop a lump on your body, whether or not it is painful and throbbing.
With an aortic aneurysm, go to the emergency room or call 911 or the local emergency number if you have pain in your belly or back that is very bad or does not go away.
With a brain aneurysm, go to the emergency room or call 911 or the local emergency number if you have a sudden or severe headache, especially if you also have nausea, vomiting, seizures, or any other nervous system symptom.
If you are diagnosed with an aneurysm that has not bled, you will need to undergo regular testing to detect if it increases in size.
Controlling high blood pressure may help prevent some aneurysms. Follow a healthy diet, get regular exercise, and keep your cholesterol at a healthy level to also help prevent aneurysms or their complications.
Do not smoke. If you do smoke, quitting will lower your risk for an aneurysm.
Aneurysm - splenic artery; Aneurysm - popliteal artery; Aneurysm - mesenteric artery
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Cheng CC, Cheema F, Fankhauser G, Silva MB. Peripheral arterial disease. In: Townsend CM Jr, Beauchamp RD, Evers BM, Mattox KL, eds. Sabiston Textbook of Surgery. 20th ed. Philadelphia, PA: Elsevier; 2017:chap 62.
Lawrence PF, Rigberg DA. Arterial aneurysms: etiology, epidemiology, and natural history. In: Sidawy AN, Perler BA, eds. Rutherford's Vascular Surgery and Endovascular Therapy. 9th ed. Philadelphia, PA: Elsevier; 2019:chap 69.
Review Date 6/23/2020
Updated by: Amit M. Shelat, DO, FACP, FAAN, Attending Neurologist and Assistant Professor of Clinical Neurology, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.