What is an abdominal aortic aneurysm?
What are the symptoms of an AAA?
Why do we get aneurysms?
Who is at risk of developing an AAA?
How common are AAAs?
Is an AAA serious?
How is an AAA diagnosed?
Do all AAA's need an operation?
What are the standard treatments?
What are the complications from surgery?
What are your treatment options if the standard treatments don't work for you?
What is the most likely expected outcome after treatment has been completed?
What is the aorta?
The aorta is the largest artery in your body. It runs from the left side of the heart, down through the chest and into the abdomen. It gives off branches to the head, upper limbs and spine in the chest. Once it enters the abdomen, branches supply the liver, spleen, kidneys and intestines before the aorta divides into the two iliac arteries which deliver blood to your legs and feet.
What is an abdominal aortic aneurysm?
An aneurysm occurs when the walls of your arteries weaken. The pressure of blood flow can cause it to stretch and balloon out to form an aneurysm. Aortic aneurysms can develop anywhere along the length of the aorta. The majority, however, are located along the abdominal aorta. These are known as Abdominal Aortic Aneurysms (AAA’s).
What are the symptoms of an AAA?
Aneurysms generally take years to develop and it is rare for them to give symptoms during this time (they are asymptomatic).
When they produce symptoms, these include:
- pain in the abdomen, back and occasionally the groin
- abdominal pulsation
Why do we get aneurysms?
Genes: Individuals with relatives affected by AAA have a higher risk of developing abdominal aortic aneurysm than the general population. They also tend to develop aneurysms at younger ages and have a higher tendency to suffer rupture. However, most patients do not have a known family history at detection.
Who is at risk of developing an AAA?
Aneurysms can affect people of any age and both sexes. However, they are most common in men, people with high blood pressure (hypertension) and those over the age of 65. They are 6 times rarer in women.
From the National Vascular Database Report 2009
You are also more likely to develop an AAA, depending on:
- if you smoke (rupture is more common in active smokers)
- high blood pressure (increases the size and risk once and aneurysm is present).
- if you have a family history of AAA - if you have a first degree relative who has had an AAA you have a higher chance of having one yourself
- if you have high cholesterol
How common are AAAs?
About 4 in 100 men over the age of 65 will develop an aneurysm, and about 1 in 100 will have a large aneurysm requiring surgery.
|
Size of Aorta |
Description |
Risk of Rupture/Year |
|
3-5.4cm |
Small/Medium aneurysm |
About 1 in 100 |
|
5.5-7cm |
Large aneurysm |
About 15 in 100 |
|
Over 7cm |
Very large aneurysm |
More than 25 in 100 |
For more information please visit the Circulation Foundation at: Circulation Foundation
Is an AAA serious?
The main concern is that if an aortic aneurysm reaches a diameter of 5 cm or more, there is a risk of it rupturing (bursting). In England and Wales between 6,000 and 8,000 people each year suffer from rupture of an AAA. The wall of the aneurysm is weaker than a normal artery wall and may not be able to withstand the pressure of blood inside. If it ruptures then severe internal bleeding occurs; this is often fatal. However, most AAAs do not rupture.
If your aortic aneurysm ruptures you will experience a sudden and severe pain in your abdomen or back. Other symptoms may include:
- dizziness,
- sweaty and clammy skin,
- rapid hear beat (tachycardia),
- shortness of breath,
- feeling faint, and
- loss of consciousness.
How is an AAA diagnosed?
The normal aorta is about 16-22mm in diameter. An abdominal aortic aneurysm is said to be present if a section of the aorta within the abdomen is 30 mm or more in diameter. This condition is often found by chance during a physical examination or scan for unrelated symptoms.
If your doctor suspects an AAA, he or she will request tests including:
- An ultrasound scan-the most common test to detect an aneurysm. It can also measure its size.
- CT scan may be performed before you have surgery. It uses X-rays to make three-dimensional images of the body. This is very useful for determining the exact position of your AAA. It also helps decide which form of treatment you can be offered. The most important feature of the scan is the maximum diameter of the aorta. This is usually about 2.5 cm (1 inch) in adults. An aneurysm is said to be present if the artery is over 3cm in diameter.
Screening
NHS Abdominal Aortic Aneurysm Screening Programme (NAAASP).
If you have an aneurysm you will not generally notice any symptoms. Screening is being offered to men, to detect aneurysms early and monitor or treat them. This greatly reduces the chances of the aneurysm causing serious problems.
The NHS AAA Screening Programme is being coordinated and led nationally. The Programme aims to cover the whole of England by April 2013.
The programme will invite all men for screening during their 65th year. Men who have an aneurysm detected through screening will be monitored until the AAA reaches a size at which treatment is advisable. This is usually 5.5 cm. AAA that cause symptoms before reaching 5.5 cm diameter will also be referred for treatment.
For more information please visit the NAAASP website at:
NHS Abdominal Aortic Aneurysm Screening Programme
If you do not live in a part of the country that is covered by the screening programme, you can still request an ultrasound scan. You will need to contact your GP for more information.
Do all AAAs need an operation?
AAA’s vary in size. Once you develop an AAA, it tends to gradually get larger. The speed at which it gets larger varies from person to person. However, on average, an AAA tends to get larger by about 10% per year. Small AAA (less than 5.5.cm in maximum diameter, have a low risk of rupture. As they enlarge beyond this the risk of rupture rises sharply.
If you have a small AAA, the risk of death caused by surgery is higher than the risk of rupture. Surgery isn't usually advised but you will need regular ultrasound checks to see if your AAA grows over time. It's also important to manage your condition by changing your lifestyle.
For larger aneurysms the risk of rupture is usually higher than the risks of surgery. However, this will depend on your personal state of health. For some people the risks of surgery will still outweigh the benefits.
Surgery is usually advised if your aneurysm is:
- larger than 5.5cm
- growing by more than 1cm per year
- causing you pain
- if you have a family history of ruptured aneurysm
What are the standard treatments?
Open surgery
Traditional surgery for aneurysm repair involves an incision in the abdomen and replacement of the affected section of vessel with a fabric tube. If the aneurysm extends into the pelvis, then a graft designed like a pair of trousers is used and may extend to the groins in some patients. The main risk of surgery is death or heart attack, and this is about 1 in 20 patients overall. Full recovery to normal levels of activity may take a few months. Once you have recovered following a successful operation, the risk of later complications is very low.
Stent graft insertion (EVAR).
With modern technology, the risks of the operation can be markedly reduced by EndoVascular Aneurysm Repair (EVAR). This minimally invasive procedure allows the graft (which is mounted on a metal scaffold called a stent) to be placed within the aorta. It is inserted into the aorta through small cuts in the arteries of the groin and positioned using X-rays. Not every patient or every aneurysm is suitable for this. In particular, aneurysms arising close to or above the kidneys are more difficult to treat in this way.
All patients treated by endovascular surgery need to be followed up postoperatively with regular scans to detect slippage or failures of the stent-graft.
Open or endovascular repair?
Open surgery carries about a 5 – 6% risk of dying within 30 days. In addition some patients may suffer heart attacks, or strokes and survive. The risk of surgery is determined mainly by your fitness prior to surgery, but also by the skill and resources of the surgical team. Impotence may occur in up to 1 in 10 men following surgery. Deep vein thrombosis is a recognized risk and most patients will have treatment to prevent this.
Endovascular repair carries a lower risk of dying at about 2% within 30 days. EVAR has a quicker recovery time because it does not involve making large surgical incisions (cuts) into the body. Complications are fewer as the operation does not interfere with the circulation as much as open surgery. However, the graft attachment is not as secure as in the open operation. As a result, you will need lifelong follow up with scans to ensure that the graft has not slipped.
Open repair is not usually recommended for people who are in a poor state of health and endovascular repair may not be possible if you have narrowed arteries.
What are the complications from surgery?
Surgery for AAA is a large and serious operation. Most procedures are done in men between 65 and 75 years old. As many people with AAA will have been smokers, they are often in poor health.
Complications include:
- Chest infection
- Wound infection or hernia
- Heart attack
- Acute kidney failure
- Deep vein thrombosis
- Death
Complications seen with EVAR
Endoleaks (blood leaks outside the stent graft). These can cause continued AAA expansion and rupture. Some will resolve spontaneously, some will require treatment.
Slipping of stent. This may require a further stent, or in a few cases, open surgery to remove the stent and replace it with a graft.
Occlusion of a limb of the stent graft. This may require angioplasty or surgery to bypass the blockage.
What are your treatment options if the standard treatments don't work for you?
For patients who are not surgical candidates (for example for patients with aneurysm smaller than 5 cm); medical treatment to prevent aneurysm expansion and rupture include:
- Stopping cigarette smoking
- Controlling high blood pressure
- Lowering high blood cholesterol
- Close monitoring of the aneurysm size with ultrasound or CT scan every 6 to 12 months (sooner in high risk patients).
What is the most likely expected outcome after treatment has been completed?
If you were treated with open repair, you will probably have to stay in hospital until the stitches have dissolved, or it is safe to remove the surgical clips, which can take between 7-10 days. It will usually take several months to make a full recovery from the operation.
If you were treated with endovascular repair, you should be able to leave hospital within 3-4 days after the surgery has been completed. Many people experience a quick recovery, however, it still make take you several months to return to the way you were before your operation.
Where to get more information:
Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two people are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.
Please note the information contained within the website is not a substitute for medical advice or treatment. The Vascular Society recommends consultation with your doctor or health care professional if you have concerns about healthcare issues.
