Abdominal Aortic Aneurysm

Abdominal aortic aneurysm refers to an enlargement or swelling in the abdominal part of the aorta, the large blood vessel that carries blood from the heart to different parts of the body. The aorta is about the thickness of a garden hose and travels from the heart through the center of the abdomen and chest.

The development of an aneurysm can occur anywhere along the aorta. When it occurs in the upper part of the aorta, it is known as a thoracic aortic aneurysm. More commonly, however, aneurysms are known to form in the lower part of the aorta and thus are called abdominal aortic aneurysms, also referred to as AAA.       

Aneurysms may form in different parts of the aorta, but abdominal aortic aneurysms are the most common. It can be a life-threatening situation if the swelling breaks open, resulting in internal bleeding.

Once the doctor identifies the abdominal aortic aneurysm, it will be closely monitored, and surgery may be planned, if required. If the abdominal aortic aneurysm ruptures, an emergency surgery would be risky at this stage.

How Big Are They?

The aneurysm can range from small (about 1.6 inches) to large (more than 2.2 inches). The swelling may remain the same without any changes, but in some it may grow rapidly and start leaking. Treatment depends on the size and growth of the aneurysm. 

Abdominal aneurysms may not show symptoms until they become large, and patients may not be aware of their existence. The abdominal aortic aneurysms often grow very slowly without any symptoms. This makes it difficult to diagnose. In some cases, the abdominal aneurysm will remain as it is without rupturing. It is difficult to predict how fast an abdominal aortic aneurysm grows; aneurysms start slowly and grow gradually, but in some cases, they can start small and remain small.

As the aneurysms grow, they produce symptoms, including:

• A pulsating feeling in the abdominal region, often near the navel
• Persistent back pain and/or abdominal pain
• A dull, persistent throbbing pain on the sides of the abdomen
• Pain in the groin that is not relieved with painkillers

Ruptured Aneurysm

A ruptured aneurysm is characterized by a sudden onset of pain. It also leads to loss of consciousness or shock, depending on the loss of blood due to internal bleeding.

Other symptoms of a ruptured aneurysm in the abdomen include: 

• Sweating
• Rapid heart beat
• Difficulty breathing
• Dizziness

The rupture of an aortic aneurysm is a medical emergency and requires surgery.

When to Visit the Doctor

Do not delay visiting the doctor if the above symptoms are present.

Males and those who smoke are at an increased chance of developing an abdominal aortic aneurysm. Men aged sixty-five to seventy-five years and who have smoked heavily throughout their lives should be screened for an abdominal aortic aneurysm. However, if you are a male and fall in this age bracket, but have never smoked, the doctor will decide if there is a need for such screening. The doctor’s decision depends on a host of factors, including if there is a family history of aneurysm. For those who have a family history of aneurysm, an ultrasound should be performed at the age of sixty.

The actual causes of abdominal aortic aneurysms are not known.

As a large amount of blood flows through the aorta, weakened walls of the blood vessel bulge outwards, forming aneurysms. A normal aorta is about two cm wide, but with a large aneurysm, it may grow up to 5.5 cm.

Infection and inflammation of the aorta may weaken the wall of the blood vessel, leading to enlargement.

Accumulation of fatty tissues within the blood vessel, called atherosclerosis, is also a possible cause of abdominal aortic aneurysms. Smoking may expedite the enlargement of the aneurysm. High blood pressure also speeds up wall damage.

In most cases, the aortic aneurysm occurs in the aorta, which is in the abdomen. The exact cause, as mentioned above, is still not known, but there are a number of factors that play a role in increasing the risk of aneurysm, including:

• High blood pressure, which is known to increase the risk of abdominal aortic aneurysms, since it can lead to damage and also weaken the walls of the aorta.
• Trauma of any kind, such as a car accident
• Tobacco use, cigarette smoking, or any other form of tobacco consumption; smoking or intake of tobacco damages the aorta and weakens its walls.
• Heredity, wherein someone in the family has had this issue previously and passes it on through the genes
• Hardening of the arteries, also called atherosclerosis, occurs when there is a fat deposit and other substances that build up on the lining of the blood vessel, which in turn leads to an increased risk in aortic aneurysm.
• An aorta infection caused by a fungal or bacterial infection, however, the chance of developing such infections is quite rare.
• Disease of the blood vessel in the aorta, wherein the blood vessels becomes inflamed 

Diagnosing abdominal aortic aneurysms is often done during a routine physical examination or when screening for another disease or condition.

Abdominal ultrasounds, CT scans, and MRIs are the confirming tests for these aneurysms.

• Abdominal ultrasound: This is one of the most common tests performed for diagnosing an abdominal aortic aneurysm. It is a painless examination where one lies on the back on an examination table, and a small amount of warm gel is applied to the abdomen. This gel helps eliminate any formation of air pockets between the body and the instrument, which is used to see the aorta. The machine is called a transducer.
• Magnetic Resonance Imaging (MRI): An MRI is another painless procedure used to diagnose this medical condition as well as determine its location and size. To conduct this test, the patient is asked to lie on a table, which is movable and slides into a tunnel. The MRI uses the magnetic pulses of radio wave energy to take pictures of the body. The doctor can inject dye into the blood vessels to make them more visible.
• Computerized tomography (CT) scan: This is a painless examination that can provide the doctor with a better, clearer image of the aorta and thus help detect its shape and size. To perform the CT scan, one would lie on a table inside a machine. The CT scan generates X-rays to produce cross-sectional images of the body. The doctor can inject a dye in the blood vessels to make it more visible.

Are You at Risk?

People who are at an increased risk of developing this condition are recommended to have an abdominal ultrasound as a screening test.

All men above the age of fifty-five with a family history of abdominal aortic aneurysms should have an abdominal ultrasound to rule out the possibility of enlargement in the aorta. Angiograms are also helpful in the detection and treatment of aneurysms in the abdomen.

Treatment of this condition is based on the size and growth of the aneurysm.

Watchful waiting is the recommended treatment for small aneurysms in the range of 1.6 inches. Patients should have an ultrasound once every six months to review symptoms and observe the growth of the aneurysm. In general, surgery is not recommended for small aneurysms.

Aneurysms in the range of 1.6 to 2.1 inches also may not need surgery. Watchful waiting is often recommended, as the risk of surgery is greater when compared to that of the aneurysm.

Large aneurysms that grow fast need surgical repair of the wall. Large aneurysms are more than 2.2 inches in size and grow more than 0.5 cm within six months. Surgery replaces the weak portion of the aorta with a graft that prevents rupture.

Surgery

The two common surgical methods are:

• Open surgical repair: In this procedure, the surgeon replaces the damaged portion of the aorta with a graft. This method has a good success rate, but the recovery period is long. Patients return to normal activities within two to three months after the surgery.
• Endovascular surgical repair: This is a less invasive procedure compared to open surgery. In this method, a synthetic graft is placed in the damaged portion of the aorta using a catheter. The recovery time for this procedure is shorter.

The type of surgery depends on a number of factors like age, other complications, and the location of the aneurysm. 

Having a healthy heart is the best way to prevent an abdominal aortic aneurysm.

Lifestyle Modification

Avoid cardiovascular risk factors like smoking, and follow a healthy diet and exercise regimen to keep blood vessels safe and healthy.

One should also control cardiovascular risk factors like hypertension, diabetes, and high cholesterol levels.

If one has any of the predisposing factors of this condition, regular screening for the presence of aneurysms, particularly after the age of sixty-five, is very helpful in the detection and treatment of aortic aneurysms.

A healthy lifestyle is the best home remedy for controlling and coping with aortic aneurysms. It would include:

• Quitting smoking
• Treating hypertension and high cholesterol levels
• Exercising regularly
• Eating a balanced diet

There are several common factors that increase the risk and affect complications of abdominal aortic aneurysms. They include:

• Smoking: Smoking or intake of tobacco is one of the biggest risk factors for abdominal aortic aneurysms and, in many cases, it leads to rupture. If one has been smoking or chewing tobacco for a longer duration, he or she is at a greater risk of developing this medical condition.
• Family history: Individuals who have a family history of aneurysms are also at a higher risk of developing this disease.
• Infection/injury: Infection in the aorta is also known to increase the risk of this disease in individuals.
• High blood pressure: Individuals with high blood pressure are also at a greater risk of getting this medical condition.
• Atherosclerosis: This is a buildup of fat and other substances, which damage the lining of the blood vessel, leading to an increased risk of aneurysm.
• Age: Aortic aneurysms are mostly seen in people aged sixty-five to seventy-five years and above.
• Gender: Abdominal aortic aneurysms are seen to develop more in males than in females.
• Race: Studies have shown that individuals who are white are at a higher risk of developing this disease.
• Other type of aneurysm: Individuals who have other types of aneurysms in another large blood vessel, such as the chest or the artery behind the knee, can also be at a higher risk of developing an aortic aneurysm.

Complications

The most common complication arising from an aortic aneurysm is the rupture of the aortic wall, resulting in internal bleeding, which is a life-threatening condition.

The risk of rupture increases with the size of the aneurysm. Blood clots may also be produced due to enlargement of the blood vessel.

Small blood clots that develop near the area of weakened aortic wall may break off and move through the blood vessel.

These clots result in pain and also hinder the flow of blood to other parts of the body like the legs, kidneys, and other organs.

Below are some of the symptoms which indicate the aortic aneurysm has ruptured:

• Clamminess
• Fast pulse rate
• Dizziness
• Sweatiness
• Low blood pressure
• Nausea
• Vomiting
• Intense or excruciating pain in the abdomen, or pain in the back, often described as a tearing sensation
• Pain in the back or legs

Abdominal aortic aneurysms can also lead to blood clots. Small blood clots can occur in the affected area of the aortic aneurysm. If the blood clot breaks loose from the inside of the wall of an aneurysm, it can cause blockage in the blood vessel elsewhere in the body. This would then lead to pain or cause a blockage of the flow of blood to other areas, such as abdominal organs, the kidneys, legs, or toes.