What is an aneurysm?

Dr. Michael L. Schwartz, MD
Vascular Surgeon

An aneurysm is a weakening of the wall of a major artery. As the wall weakens, it can balloon out forming an aneurysm. Typically, the aneurysm involves one of the largest arteries in the body, the aorta. If the aneurysm grows too big, it can burst.

An aneurysm is when the wall of an artery weakens and balloons out or ruptures.
An aneurysm is when an artery expands to 1.5 times its normal size. Find out where vascular surgeons look for aneurysms in this video with Charles Bailey, MD, of Brandon Regional Hospital.
Dr. Geoffrey P. Colby, MD

Arteries are the high-flow, high-pressure blood vessels inside the head that carry blood from the heart. An aneurysm is a weakened, ballooned-out spot in a brain artery. We don't fully understand how the original weakness in the blood vessel first develops. It is possible that people are born with a slightly weakened spot in a brain blood vessel, and a variety of risk factors determine whether that spot develops into an aneurysm. Most commonly, an aneurysm forms at the branching point of two arteries. With a lifetime of blood pressure pounding away on that weak spot, it gradually expands and forms an aneurysm. Once it weakens sufficiently, it can cause a hemorrhage. Further research is needed to better understand this process.

An aneurysm is a localized weakness and swelling of the wall of a blood vessel or of the heart wall. An aneurysm can result from a physical injury, a disease such as atherosclerosis, smoking, or a birth defect.

An aneurysm occurs when the force of blood flow pushes against a weakened artery wall and causes it to bulge. If left untreated, an aneurysm can rupture and cause internal bleeding. If the internal bleeding is severe enough, ruptures can be fatal. Aneurysms can occur in the aorta—the artery responsible for delivering blood from your heart to the rest of your body—the brain, and other places in your body.

Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)

Watch this video to learn more from Dr. Mehmet Oz about an aneurysm.

An aneurysm is a large pocket or bubble in a blood vessel that forms a weak spot in the vessel's wall, which can be life-threatening if it ruptures; some people may have a genetic tendency to develop aneurysms.

Emilia Klapp
Nutrition & Dietetics Specialist

An aneurysm is a ballooning of the artery, often caused by increased pressure on the inner walls of the blood vessels through a condition such as high blood pressure, or hypertension. This ballooning may cause the blood vessel to rupture, causing internal bleeding.

Dr. Emily A. Farkas, MD
Cardiothoracic Surgeon

An aneurysm is an enlargement of a blood vessel that can occur anywhere in the body, but is most common in the brain, chest, or abdomen. An aneurysm is sometimes referred to as a circumferential ‘swelling’ or ‘dilation’. If you imagine that one of our body’s larger blood vessels may originally be the diameter of a nickel, an aneurysm can cause that blood vessel to enlarge to the diameter of a quarter or a silver dollar over time. The largest blood vessel in the body, called the aorta, can enlarge to the diameter of a soda can or even larger.

When a blood vessel is stretched or enlarged from an aneurysm, it makes the wall of that blood vessel weaker than normal and susceptible to tearing (called a dissection) or rupturing. In most cases, the enlargement happens slowly over several months or years, not days or weeks. Based on the location, size, and growth rate of the blood vessel, your doctor may recommend regular check-ups and pictures of the aneurysm and/or surgery when the enlargement is advanced.

An aneurysm, a bulge or blister in an artery wall, can develop as the vessel wall becomes stretched and weakened from an infection, injury, or high blood pressure or because of a genetic weakness in the artery. Aneurysms can become life-threatening when they rupture and hemorrhage. Aneurysms can also burst and leak blood into the cerebrospinal fluid, even the brain itself. Arterial bleeding can cause increased pressure in the brain cavity and reduce the flow of blood to brain tissue. In both these cases the result may be a stroke.

A network of arteries and other blood vessels runs through your body, carrying blood from your heart to the rest of your body. An aneurysm is a bulge in a blood vessel wall. The artery wall stretches outward as the pressure of the blood it carries pushes against a weak portion in the wall. If the artery wall is very thin, the aneurysm can rupture, causing internal bleeding. While aneurysms can occur in various places throughout the body, aneurysms in the brain artery, heart artery and abdominal aorta are common and can be life threatening particularly if they rupture.

An aneurysm is an outpouching of an artery wall. An aortic aneurysm is an outpouching of the aortic wall greater than 1.5 times the normal wall diameter. An aortic aneurysm can be dangerous as it can rupture and lead to massive bleeding, and ultimately death.

An aneurysm is when the wall of an artery weakens, bulges and bursts. It's the third most common cause of sudden death in the U.S.

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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.