Definition
An aortic aneurysm is a weakened and bulging area in the aorta, the major blood vessel that feeds blood to the body. The aorta, about the thickness of a garden hose, runs from your heart through the center of your chest and abdomen. Because the aorta is the body's main supplier of blood, a ruptured aortic aneurysm can cause life-threatening bleeding. Although you may never have symptoms, finding out you have an aortic aneurysm can be frightening.
Symptoms
Aortic aneurysms often grow slowly and usually without symptoms, making them difficult to detect. Some aneurysms will never rupture. Many start small and stay small, although many expand over time. Some aortic aneurysms enlarge slowly, increasing less than half an inch (1.2 centimeters) a year. Others expand at a faster rate, which increases the risk of rupture. How quickly an aortic aneurysm may grow is difficult to predict.
As an aortic aneurysm grows, some people may notice:
- A pulsating feeling near the navel, if the aneurysm occurs in the abdomen
- Tenderness or pain in the abdomen or chest
- Back pain
Aneurysms can develop anywhere along the aorta, but most occur in the abdomen and are called abdominal aortic aneurysms. Aneurysms that occur in the part of the aorta that's higher up in your chest are called thoracic aortic aneurysms.
When to see a doctor
You should see your doctor if you have any of the symptoms listed above.
Anyone age 60 and older who has risk factors for developing an aortic aneurysm should consider regular screening for the condition. Men ages 65 to 75 who have ever smoked should have a one-time screening for abdominal aortic aneurysm using abdominal ultrasound. Men age 60 and older with a family history of abdominal aortic aneurysm should also consider screening.
If you have a family history of aortic aneurysm, your doctor may recommend regular ultrasound exams to screen for aortic aneurysm.
Causes
Abdominal aortic aneurysms
About 75 percent of all aortic aneurysms occur in the part of your aorta that's in your abdomen. Although the exact cause of abdominal aortic aneurysms is unknown, researchers think a number of factors can play a role, including:
- Tobacco use. Cigarette smoking and other forms of tobacco use make up one of the most significant factors involved in the development of aortic aneurysms. In addition to the damaging effects that smoking causes directly to the arteries, smoking contributes to atherosclerosis and high blood pressure, and causes aneurysms to grow faster.
- High blood pressure. High blood pressure, especially if poorly controlled, increases the risk of developing an aortic aneurysm.
- Infection in the aorta (vasculitis). In rare cases, aortic aneurysm may be caused by an infection or inflammation (vasculitis) that weakens a section of the aortic wall. There is often a pattern of aneurysm development among family members, meaning it could be genetic.
Thoracic aortic aneurysms
About 25 percent of aortic aneurysms occur higher up in your chest (the thoracic area of the aorta). While the same risk factors associated with abdominal aortic aneurysms can contribute to thoracic aortic aneurysms, there are some additional factors that can lead to a thoracic aortic aneurysm, including:
- Marfan syndrome. People who are born with Marfan syndrome, a genetic condition that affects the connective tissue in the body, are particularly at risk of a thoracic aortic aneurysm. Those with Marfan syndrome may have a weakness in the aortic wall that makes them more susceptible to aneurysm. People with Marfan syndrome often have distinct physical traits, including tall stature, very long arms, a deformed breastbone and eye problems.
- Previous injury to the aorta. You're more likely to have a thoracic aortic aneurysm if you've had previous problems with your aorta, such as a tear in the wall of the aorta (aortic dissection).
- Traumatic injury. Some people who are injured in falls or motor vehicle crashes develop thoracic aortic aneurysms.
An aortic aneurysm is different from a condition called aortic dissection. Aortic dissection often occurs in the same place many aneurysms occur. In aortic dissection, a tear occurs in the wall of the aorta. This causes bleeding into and along the aortic wall and, in some cases, completely outside the aorta (rupture). Aortic dissection is a life-threatening emergency.
Risk factors
Aortic aneurysm risk factors include:
- Age. Abdominal aortic aneurysms occur most often in people age 60 and older.
- Tobacco use. Tobacco use is a strong risk factor for the development of an aortic aneurysm. The longer you've smoked or chewed tobacco, the greater your risk.
- High blood pressure. Increased blood pressure damages the blood vessels in the body, raising your chances of developing an aneurysm.
- Atherosclerosis. Atherosclerosis, the buildup of fat and other substances that can damage the lining of a blood vessel, increases your risk of an aneurysm.
- Being male. Men develop aortic aneurysms five to 10 times more often than women do. However, women with aortic aneurysms have a higher risk of rupture than do men.
- Race. Aortic aneurysms occur more commonly in whites than in people of other races.
- Family history. People who have a family history of aortic aneurysm are at increased risk of having one. People who have a family history of aneurysms tend to develop aneurysms at a younger age and are at higher risk of rupture.
ortic aneurysm risk factors include:
- Age. Abdominal aortic aneurysms occur most often in people age 60 and older.
- Tobacco use. Tobacco use is a strong risk factor for the development of an aortic aneu
Complications
Tears in the wall of the aorta (dissection) and rupture of the aorta are the main complications of abdominal aortic aneurysm. A ruptured aortic aneurysm can lead to life-threatening internal bleeding. In general, the larger the aneurysm, the greater the risk of rupture.
Signs and symptoms that your aortic aneurysm has burst include:
- Sudden, intense and persistent abdominal, chest or back pain
- Pain that radiates to your back or legs
- Sweatiness
- Clamminess
- Dizziness
- Low blood pressure
- Fast pulse
- Loss of consciousness
- Shortness of breath
Another complication of aortic aneurysms is the risk of blood clots. Small blood clots can develop in the area of the aortic aneurysm. If a blood clot breaks loose from the inside wall of an aneurysm and blocks a blood vessel elsewhere in your body, it can cause pain or block the blood flow to the legs, toes or abdominal organs.
Preparing for your appointment
Since many aortic aneurysms are found during a routine physical exam, or while your doctor is looking for another condition, there are no special preparations necessary. If you're being screened for an aortic aneurysm, your doctor will likely ask if anyone in your family has ever had an aortic aneurysm, so have that information ready.
You should ask about the size of your aneurysm, whether your doctor has noticed any changes, and how frequently you should visit your doctor for follow-up appointments if he or she doesn't share this information with you.
If you're having an abdominal ultrasound to diagnose an aortic aneurysm, it's likely your doctor will tell you to not eat or drink anything for nine to 12 hours before your ultrasound. Most ultrasound exams are done in the morning so that you can eat soon afterward.
Tests and diagnosis
Most abdominal aortic aneurysms are found during an examination for another reason. For example, during a routine exam, your doctor may feel a pulsating bulge in your abdomen, though it's unlikely your doctor will be able to hear signs of an aneurysm through a stethoscope. Aortic aneurysms are often found during routine medical tests, such as a chest X-ray or ultrasound of the heart or abdomen, sometimes ordered for a different reason.
If your doctor suspects that you have an aortic aneurysm, specialized tests can confirm it. These tests might include:
- Echocardiogram. This test is a sonogram of your heart. It uses sound waves to capture real-time images of your heart in motion. Echocardiograms show how well your heart chambers and valves are working. Occasionally, to better see your aorta, your doctor may recommend a transesophageal echocardiogram — in which the sound waves are generated from within your body by a device threaded down your esophagus.
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Abdominal ultrasound. This exam can help diagnose an abdominal aortic aneurysm. During this painless exam, you lie on your back on an examination table and a small amount of warm gel is applied to your abdomen. The gel helps eliminate the formation of air pockets between your body and the instrument the technician uses to see your aorta, called a transducer. The technician presses the transducer against your skin over your abdomen, moving from one area to another. The transducer sends images to a computer screen that the technician monitors to check for a potential aneurysm.
In the United States, Medicare offers a one-time ultrasound screening for abdominal aortic aneurysm for people who qualify and request the screening within six months of enrolling in a Medicare program. Men who have smoked at least 100 cigarettes in their lifetimes and anyone with a family history of abdominal aortic aneurysm are eligible for the benefit.
- Computerized tomography (CT) scan. This painless test can provide your doctor with clear images of your aorta. During a CT scan, you lie on a table inside a doughnut-shaped machine called a gantry. Detectors inside the gantry measure the radiation that has passed through your body and converts it into electrical signals. A computer gathers these signals and assigns them a color ranging from black to white, depending on signal intensity. The computer then assembles the images and displays them on a computer monitor.
- Magnetic resonance imaging (MRI). MRI is another painless imaging test. Most MRI machines contain a large magnet shaped like a doughnut or tunnel. You lie on a movable table that slides into the tunnel. The magnetic field aligns atomic particles in some of your cells. When radio waves are broadcast toward these aligned particles, they produce signals that vary according to the type of tissue they are. Your doctor can use the images produced by the signals to see if you have an aneurysm.
Regular screening for people at risk of abdominal aortic aneurysms
Because aortic aneurysms often don't cause symptoms, anyone age 60 and older who has risk factors for developing an aortic aneurysm should consider regular screening for the condition. Men ages 65 to 75 who have ever smoked should have a one-time screening for abdominal aortic aneurysm using abdominal ultrasound. Men age 60 and older with a family history of abdominal aortic aneurysm should also consider screening.
Screening for thoracic aortic aneurysms
Conditions that cause an aneurysm to occur higher up in your chest (thoracic aortic aneurysm) can run in families. Because of this, your doctor may recommend you have tests to check for thoracic aortic conditions if a first-degree relative, such as a sibling, son or daughter, has Marfan syndrome or another condition that could cause a thoracic aortic aneurysm. Additional tests to check for thoracic aortic aneurysms include:
- Imaging tests. Your doctor may recommend that your first-degree relatives have an echocardiogram or another type of imaging test to check for Marfan syndrome or another thoracic aortic condition. If your doctor finds you have an enlarged aorta or an aneurysm, you'll likely need another imaging test within six months to make sure your aorta hasn't grown larger.
- Genetic testing. One cause of thoracic aortic aneurysms, Marfan syndrome, is a hereditary condition. Right now, there's no genetic test that alone can definitely establish or rule out a diagnosis of Marfan syndrome. However, genetic testing can aid in the diagnosis of Marfan syndrome, especially if you do not have symptoms. In addition, you may want to consider genetic testing and genetic counseling before starting a family, to see what your chances are of passing on Marfan syndrome to your future children.
Treatments and drugs
The goal of treatment is to prevent your aneurysm from rupturing. Generally, your treatment options are to watch and wait or to have surgery. Your decision depends on the size of the aortic aneurysm and how fast it's growing. Here are the general guidelines for treating abdominal aortic aneurysms:
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Small aneurysm. If you have a small aortic abdominal aneurysm — about 1.6 inches, or 4 centimeters (cm), in diameter or smaller — and you have no symptoms, your doctor may suggest a watch-and-wait (observation) approach, rather than surgery. In general, surgery isn't needed for small aneurysms because the risk of surgery outweighs the risk of rupture.
If you choose this approach, your doctor will monitor your aneurysm with periodic ultrasounds, usually every six to 12 months and encourage you to report immediately if you start having abdominal tenderness or back pain — potential signs of a dissection or rupture.
- Medium aneurysm. A medium aneurysm measures between 1.6 and 2.2 inches (4 and 5.5 cm). It's less clear how the risks of surgery versus waiting stack up in the case of a medium-size aortic abdominal aneurysm. You'll need to discuss the benefits and risks of waiting versus surgery and make a decision with your doctor.
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Large or fast-growing aneurysm. If you have an aneurysm that is large (larger than 2.2 inches, or 5.5 cm) or growing rapidly (more than 0.5 cm over six months), leaking, tender or painful, you'll probably need surgery. Surgery to repair an aortic aneurysm involves removing the damaged section of the aorta and replacing it with a synthetic tube (graft), which is sewn into place. This procedure requires open-abdominal or open-chest surgery, and it will take you several months to fully recover.
It's also possible you could have a less invasive procedure called endovascular surgery to repair your aneurysm. Doctors attach a synthetic graft to the end of a thin tube (catheter) that's inserted through an artery in your leg and threaded up into your aorta. The graft — a woven tube covered by a metal mesh support — is placed at the site of the aneurysm and fastened in place with small hooks or pins. The graft reinforces the weakened section of the aorta to prevent rupture of the aneurysm.
Recovery time for people who have endovascular surgery is shorter than for people who have open-chest or abdominal surgery - about one or two weeks compared with six weeks with open surgery. Research has shown that people who have endovascular surgery also have lower rates of death and complications due to their aneurysms.
Thoracic aortic aneurysm treatment
If you have a thoracic aortic aneurysm, surgery is generally recommended if your aneurysm is 2.2 inches (5.5 cm) and larger. If you have Marfan syndrome or a family history of aortic dissection, your doctor may recommend surgery for smaller aneurysms, as well.
Emergency surgery
Although it's possible to repair a ruptured aortic aneurysm with emergency surgery, the risk is much higher and there is less chance of survival. Many people who experience a ruptured aortic aneurysm die before they reach the hospital.
Recommendations for surgical treatment of thoracic aortic aneurysms depend on whether you have another condition, such as Marfan syndrome, and location of the aneurysm.
Prevention
There are no medications you can take to prevent an aortic aneurysm. Researchers think that statin medications and some antibiotics can slow the growth of small aortic aneurysms. There's also some evidence that the angiotensin receptor blocker losartan (Cozaar) may prevent aneurysm formation.
For now the best approach to prevent an aortic aneurysm is to keep your blood vessels as healthy as possible. That means taking these steps:
- Keep your blood pressure under control.
- Don't smoke.
- Get regular exercise.
- Reduce cholesterol and fat in your diet.
It's especially important to quit using tobacco because smoking or chewing tobacco can increase the chances your aneurysm will grow.
If you have some risk factors for aortic aneurysm, talk to your doctor. If you are at risk, your doctor may recommend additional measures, including medications to lower your blood pressure and relieve stress on weakened arteries. You may also want to consider screening ultrasounds every few years.
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