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Aneurysms of Arteries in the Arms, Legs, Heart, and Brain


The Manual's Editorial Staff

Last full review/revision Sep 2019
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What is an aneurysm?

An aneurysm is a bulge in an artery. It happens from a weak spot in the artery wall. An artery is a blood vessel that carries blood from your heart to the different parts of your body. Veins are the blood vessels that carry blood back to your heart. Veins don't get aneurysms.

  • Aneurysms can happen in any artery

  • You might be born with an aneurysm, but most happen when you're older because you have hardening of the arteries (atherosclerosis)

  • Aneurysms sometimes suddenly burst open or cause blood clots that block the artery

  • Doctors do surgery to close or remove the aneurysm

  • Sometimes doctors can put a small metal coil in the aneurysm to close it without doing surgery

You can also have an aneurysm in your aorta. Your aorta is the main artery that carries blood from your heart.

What causes aneurysms?

An aneurysm may be caused by:

  • A weakness in the artery wall that you were born with

  • A buildup of fatty material inside your arteries (atherosclerosis, also called hardening of the arteries)

  • An injury to an artery from a knife or gunshot

  • A bacterial or fungal infection in your artery—this can happen from injecting street drugs, such as heroin

What are the symptoms of an aneurysm?

Some aneurysms don't cause any symptoms. Symptoms depend on where the aneurysm is in your body and on its size.

An aneurysm in your leg usually doesn't cause symptoms unless a blood clot forms in the aneurysm. If you have a blood clot, it may leave the aneurysm and block blood flow in your foot and make it painful, numb, and cool.

An aneurysm in your neck can form a blood clot that travels to your brain and cause a stroke.

An aneurysm in your brain may cause a headache. If a brain aneurysm bursts it will cause bleeding around your brain (called a subarachnoid hemorrhage) that can be fatal.

Sometimes an aneurysm gets infected. Infected aneurysms cause pain and swelling.

How can doctors tell if I have an aneurysm?

Sometimes doctors can feel a throbbing mass in your artery by examining you. They may also do:

How do doctors treat aneurysms?

Aneurysms in different locations are treated differently:

  • Aneurysms in the brain: Surgery to close the aneurysm with a metal clip, or to place a metal coil into the aneurysm through a small tube (catheter) passed through an artery in your neck

  • Aneurysms in your arm or leg: Surgery to remove the aneurysm and replace it with a piece of artificial blood vessel (graft). Sometimes doctors can put a graft in through a catheter passed through your artery.

You'll get antibiotics or antifungal medicines for an infected aneurysm.

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