What is an aneurysm?

An aneurysm is the dilation - thinning and ballooning or bulging out - in part of the wall of a vein, artery, or the heart. An aneurysm may be small and not cause any symptoms.

What causes an aneurysm to form?

An aneurysm may be caused or aggravated by disease (such as atherosclerosis or hypertension), injury, or an abnormality present at birth.

How are aneurysms diagnosed?

In addition to a complete medical history and physical examination, diagnostic procedures for an aneurysm may include any, or a combination of, the following:

  • computed tomography scan (Also called a CT or CAT scan.) - a diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body.

    A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than general x-rays.
  • magnetic resonance imaging (MRI) - a diagnostic procedure that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures within the body.
  • echocardiogram (also known as echo) - a procedure that evaluates the structure and function of the heart by using sound waves recorded on an electronic sensor that produce a moving picture of the heart and heart valves.

What dangers do aneurysms present?

The danger from an aneurysm is that it will continue to bulge and may burst. When an aneurysm in a large blood vessel or in the heart bursts, a person could bleed to death. When an aneurysm bursts in the brain, a stroke (brain attack) can result.