Types of Aneurysm
Aortic Aneurysms
The two types of aortic aneurysm are abdominal
aortic aneurysm (AAA) and thoracic aortic aneurysm (TAA).
Aortic Aneurysms
Figure A shows a normal aorta.
Figure B shows a thoracic aortic aneurysm (which is located behind the heart).
Figure C shows an abdominal aortic aneurysm located below the arteries that
supply blood to the kidneys.
Abdominal Aortic Aneurysms
An aneurysm that occurs in the part of the aorta
that's located in the abdomen is called an abdominal aortic aneurysm. AAAs
account for 3 in 4 aortic aneurysms. They're found more often now than in the
past because of computed tomography (to-MOG-rah-fee), or CT, scans done for
other medical problems.
Small AAAs rarely rupture. However, an AAA can grow
very large without causing symptoms. Thus, routine checkups and treatment for
an AAA are important to prevent growth and rupture.
Thoracic Aortic Aneurysms
An aneurysm that occurs in the part of the aorta
that's located in the chest and above the diaphragm is called a thoracic aortic
aneurysm. TAAs account for 1 in 4 aortic aneurysms.
TAAs don't always cause symptoms, even when they're
large. Only half of all people who have TAAs notice any symptoms. TAAs are
found more often now than in the past because of
chest
CT scans done for other medical problems.
With a common type of TAA, the walls of the aorta
weaken, and a section close to the heart enlarges. As a result, the valve
between the heart and the aorta can't close properly. This allows blood to leak
back into the heart.
A less common type of TAA can develop in the upper
back, away from the heart. A TAA in this location may result from an injury to
the chest, such as from a car crash.
Other Types of Aneurysms
Brain Aneurysms
When an aneurysm occurs in an artery in the brain,
it's called a
cerebral (seh-RE-bral or SER-eh-bral) aneurysm or brain
aneurysm. Brain aneurysms also are sometimes called berry aneurysms because
they're often the size of a small berry.
Brain Aneurysm
The illustration shows a typical
location of a brain (berry) aneurysm in the arteries supplying blood to the
brain. The inset image shows a closeup view of the sac-like aneurysm.
Most brain aneurysms cause no symptoms until they
become large, begin to leak blood, or rupture. A ruptured brain aneurysm causes
a
stroke.
Peripheral Aneurysms
Aneurysms that occur in arteries other than the
aorta and the brain arteries are called peripheral aneurysms. Common locations
for peripheral aneurysms include the popliteal (pop-li-TE-al), femoral
(FEM-o-ral), and carotid (ka-ROT-id) arteries.
The popliteal arteries run down the back of the
thighs, behind the knees. The femoral arteries are the main arteries in the
groin. The carotid arteries are the two main arteries on each side of your
neck.
Peripheral aneurysms arent as likely to
rupture or dissect as aortic aneurysms. However, blood clots can form in
peripheral aneurysms. If a blood clot breaks away from the aneurysm, it can
block blood flow through the artery.
If a peripheral aneurysm is large, it can press on a
nearby nerve or vein and cause pain, numbness, or swelling.
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