Thoracic Aortic Aneurysm and Aortic Dissection
What is a thoracic aortic aneurysm?
The aorta is the largest blood vessel in the body. It delivers oxygenated blood from
the heart to the rest of the body. An aortic aneurysm is a bulging, weakened area
in the wall of the aorta. Over time, the blood vessel balloons and is at risk for
bursting (rupture) or separating (dissection). This can cause life threatening bleeding
and potentially death.
"Thoracic" refers to the part of the aorta that runs through the chest (thoracic aortic
aneurysm). Aneurysms occur more often in the portion of the aorta that runs through
the abdomen (abdominal aortic aneurysm).
Once formed, an aneurysm will gradually increase in size and get progressively weaker.
Treatment for a thoracic aneurysm may include surgical repair or removal of the aneurysm,
or inserting a metal mesh coil (stent) to support the blood vessel and prevent rupture.
What causes a thoracic aortic aneurysm to form?
Different disease processes can cause thoracic aortic aneurysms including:
What are the symptoms of a thoracic aortic aneurysm?
Thoracic aortic aneurysms may not cause symptoms. When symptoms do occur, they may
be related to the location, size, and how fast the aneurysm is growing.
Sudden, severe pain associated with a thoracic aneurysm may be a sign of a life-threatening
Symptoms of a thoracic aneurysm may include:
Pain in the jaw, neck, or upper back
Pain in the chest or back
Wheezing, coughing, or shortness of breath as a result of pressure on the trachea
Hoarseness as a result of pressure on the vocal cords
Trouble swallowing due to pressure on the esophagus
The symptoms of a thoracic aortic aneurysm may look like other conditions. See your doctor
for a diagnosis.
How is a thoracic aortic aneurysm diagnosed?
Your doctor will do a complete medical history and physical exam. Other possible tests
Computed tomography scan (also called a CT or CAT scan). This test uses X-rays and computer technology to
make horizontal, or axial, images (often called slices) 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 standard X-rays.
Magnetic resonance imaging (MRI). This test uses a combination of large magnets, radiofrequencies, and a computer to
produce detailed images of organs and structures within the body.
Echocardiogram (also called echo). This test evaluates the structure and function of the heart by using sound waves
recorded on an electronic sensor that make a moving picture of the heart and heart
valves, as well as the structures within the chest, such as the lungs and the area
around the lungs and the chest organs.
Transesophageal echocardiogram (TEE). This test uses echocardiography to check for aneurysm, the condition of heart valves,
or presence of a tear of the lining of the aorta. TEE is done by inserting a probe
with a transducer on the end down the throat.
Chest X-ray. This test uses invisible electromagnetic energy beams to make images of internal tissues,
bones, and organs onto film.
Arteriogram (angiogram). This is an X-ray image of the blood vessels that is used to assess conditions such
as aneurysm, narrowing of the blood vessel, or blockages. A dye (contrast) will be
injected through a thin, flexible tube placed in an artery. The dye makes the blood
vessels visible on an X-ray.
What is the treatment for thoracic aortic aneurysm?
Treatment may include:
Monitoring with MRI or CT. These tests are done to check the size and rate of growth of the aneurysm.
Managing risk factors. Steps, such as quitting smoking, controlling blood sugar if you have diabetes, losing
weight if overweight, and eating a healthy diet may help control the progression of
Medicine. Used to control factors such as high cholesterol or high blood pressure.
Thoracic aortic aneurysm open repair. The type of surgery will depend on the location and type of aneurysm, and your overall
health. For an ascending or aortic arch aneurysm, a large incision may be made through
the breastbone. If an ascending aneurysm involves damage to the aortic valve of the
heart, the valve may be repaired or replaced during the procedure. For a descending
aneurysm, a large incision may extend from the back under the shoulder blade around
the side of the rib cage to just under the breast. This lets the surgeon to see the
aorta directly to repair the aneurysm.
Endovascular aneurysm repair (EVAR). EVAR requires only small incisions in the groin. Using X-ray guidance and specially-designed
instruments, the surgeon can repair the aneurysm by inserting a metal mesh coil, called
a stent-graft, inside the aorta. Not all thoracic aneurysms can be repaired by means
A small aneurysm or one that doesn't cause symptoms may not require surgical treatment
until it reaches a certain size or is rapidly increasing in size over a short period
of time. Your doctor may recommend "watchful waiting." This may include a CT scan
or MRI scan every 6 months to closely monitor the aneurysm, and blood pressure medicine
may be used to control high blood pressure.
Your doctor may recommend surgery if the aneurysm is causing symptoms or is large.
What is aortic dissection?
An aortic dissection starts with a tear in the inner layer of the aortic wall of the thoracic
aorta. The aortic wall is made up of 3 layers of tissue. When a tear occurs in the
innermost layer of the aortic wall, blood is then channeled into the wall of the aorta
separating the layers of tissues. This generates a weakening in the aortic wall with
a potential for rupture. Aortic dissection can be a life-threatening emergency. The
most commonly reported symptom of an acute aortic dissection is severe, constant chest
or upper back pain, sometimes described as "ripping" or "tearing." The pain may move
from one place to another.
When a diagnosis of aortic dissection is confirmed, immediate surgery or stenting
is usually done.
What causes aortic dissection?
The cause of aortic dissection is unclear. However, there are several risk factors
associated with aortic dissection, such as:
High blood pressure
Connective tissue disorders, such as Marfan disease, Ehlers-Danlos syndrome, and Turner
Cystic medial disease (a degenerative disease of the aortic wall)
Aortitis (inflammation of the aorta)
Bicuspid aortic valve (only 2 flaps in the aortic valve, rather than the normal 3)
Coarctation of the aorta (narrowing of the aorta)
Excess fluid or volume in the circulation (hypervolemia)
Polycystic kidney disease (a genetic disorder characterized by the growth of numerous
cysts filled with fluid in the kidneys)