Table of Contents

About abdominal aortic aneurysms

What is an Abdominal Aortic Aneurysm (AAA)?

An abdominal aortic aneurysm (AAA) is a condition characterized by the swelling of the abdominal aorta – the primary blood vessel that transports blood away from the heart through the abdomen and to the rest of the body. Typically, the abdominal aorta is about 2cm wide (similar to the diameter of a garden hose). However, in the case of an aneurysm, it may swell to over 5.5cm, which is considered a large AAA and a serious health risk.

Risks of a Large AAA

While large aneurysms are relatively uncommon, they can pose a significant threat if they burst. A rupture can lead to massive internal bleeding and is often fatal. The bulging and weakening of the aorta’s wall may result from various factors, with smoking and high blood pressure contributing to an increased risk of aneurysm formation.

Who is Most at Risk?

Men over the age of 65 are particularly vulnerable to AAA, with ruptures accounting for more than 1 in 50 deaths in this group. Because of this, men turning 65 are routinely invited for a screening test via a quick ultrasound scan, typically lasting 10-15 minutes.

Symptoms of an AAA

In many cases, an abdominal aortic aneurysm shows no noticeable symptoms. However, as the aneurysm grows, some individuals may experience:

Abdominal pain or a pulsating sensation in the tummy.
Persistent back pain.

When an aneurysm ruptures, the symptoms can be more severe and life-threatening:

Sudden and intense abdominal pain.
Rapid internal bleeding, often resulting in an emergency. Immediate medical assistance by calling 999 is crucial.

Causes of AAA

The exact cause of AAA remains unclear. However, some significant risk factors include:

Age and Gender: Increasing age and being male are the most significant risk factors.
Smoking.
High blood pressure and high cholesterol.
Family history of aortic aneurysms.

Diagnosis of AAA

Since most AAAs are asymptomatic, they are often discovered through routine screenings or by a healthcare professional who notices a pulsating abdominal sensation. The ultrasound scan measures the size of the abdominal aorta, confirming the presence of an aneurysm.

Treating an AAA

Treatment focuses on preventing rupture. If a large AAA is detected:

Surgery may be recommended to replace the weakened aortic segment with synthetic tubing.
Non-surgical options include medication to manage cholesterol and blood pressure, as well as lifestyle changes like quitting smoking.
Regular ultrasound monitoring is essential to track the size of the aneurysm.

Prevention Tips

Reducing the risk of developing an aneurysm or preventing an existing one from worsening involves:

Quitting smoking.
Eating a balanced, low-fat diet.
Regular physical activity.
Maintaining a healthy weight.

Symptoms of an abdominal aortic aneurysm (AAA)

Symptoms of an Unruptured AAA

Most abdominal aortic aneurysms (AAA) do not cause noticeable symptoms unless the aneurysm becomes significantly large. In such cases, possible symptoms include:

Pulsating sensation in the abdomen, usually near the belly button, which may be felt upon touch.
Persistent back pain.
Chronic abdominal pain.

If you experience any of these symptoms, it is important to consult your GP (General Practitioner) as soon as possible for an evaluation.

Symptoms of a Ruptured AAA

When an abdominal aortic aneurysm ruptures, it is a life-threatening emergency that requires immediate attention. The symptoms of a rupture include:

Sudden and severe pain in the middle or side of the abdomen.
In men, the pain may radiate down into the scrotum.
Dizziness or feeling faint.
Sweaty and clammy skin.
Rapid heartbeat (tachycardia).
Shortness of breath.
Loss of consciousness.

Emergency Action for a Ruptured AAA

A ruptured aortic aneurysm is a critical medical emergency. Around 80% of individuals with a rupture either die before reaching the hospital or do not survive emergency surgery. For this reason, the NHS AAA Screening Programme was introduced to detect and treat large aneurysms before they become life-threatening.

Causes of an Abdominal Aortic Aneurysm (AAA)

The aorta is the body’s largest blood vessel, responsible for transporting oxygen-rich blood from the heart to the rest of the body. An abdominal aortic aneurysm (AAA) forms when a portion of the aortic wall becomes weakened. As blood flows through the aorta, pressure on the weakened spot can cause it to bulge outward, resulting in an aneurysm.

The typical width of the abdominal aorta is about 2cm (similar to a garden hosepipe), but it may expand to over 5.5cm in cases of large aneurysms, which are considered particularly serious by medical professionals.

Risk Factors for Developing an AAA

While the exact cause of aortic wall weakening remains unclear, certain risk factors increase the likelihood of developing an AAA:

Age and Gender

Increasing Age: People over 75 are seven times more likely to have an AAA compared to those under 55.
Gender: Men are approximately six times more likely to be diagnosed with an AAA than women.

Modifiable Risk Factors

Some risk factors can be controlled to reduce your risk of developing an AAA. Key modifiable factors include:

Smoking

Smokers have seven times the risk of developing an AAA compared to non-smokers.
Regularly smoking more than 20 cigarettes a day can increase the risk tenfold.
Tobacco smoke contains substances that can damage and weaken the aorta’s walls, contributing to aneurysm formation.

Atherosclerosis

Atherosclerosis is a condition characterized by the buildup of fatty deposits (plaques) such as cholesterol in the arteries, which can cause them to narrow and harden.
When plaques form in the aorta, it may widen in an attempt to maintain blood flow, weakening the vessel walls over time.
Risk factors for atherosclerosis include smoking, a high-fat diet, and high blood pressure.

High Blood Pressure (Hypertension)

High blood pressure not only contributes to atherosclerosis but also places extra stress on the aortic walls, increasing the risk of aneurysm formation.

Family History

A family history of AAAs significantly raises your risk. Research shows that individuals with a sibling who has an AAA are eight times more likely to develop one themselves.
This suggests a genetic predisposition, although no specific genes have been identified yet.

Diagnosing an Abdominal Aortic Aneurysm (AAA)

Why is Diagnosis Important?

An abdominal aortic aneurysm (AAA) typically causes no noticeable symptoms, making diagnosis challenging without routine screening. AAAs are often detected during a general physical examination when a GP (General Practitioner) notices a distinctive pulsating sensation in the abdomen.

How is AAA Diagnosed?

Ultrasound Scan
The primary method for diagnosing an AAA is through an ultrasound scan. This quick, painless procedure not only confirms the presence of an aneurysm but also measures its size, a critical factor in determining the appropriate course of treatment.

Screening for AAAs

In the UK, all men aged 65 and over are offered an ultrasound screening to check for AAAs. This proactive approach aims to detect and manage aneurysms before they pose a serious health risk.

Men turning 65 will automatically receive an invitation for screening.
Men over 65 who have not been screened can self-refer by contacting their local NHS AAA screening service.

Regular screening ensures that AAAs are identified early, improving the chances of effective treatment and preventing life-threatening complications.

Treating an Abdominal Aortic Aneurysm (AAA)

Treatment Overview

Treatment for an abdominal aortic aneurysm (AAA) depends on factors such as the aneurysm’s size, your age, and overall health. Generally:

Large AAAs (5.5cm or larger) often require surgical intervention to either strengthen or replace the affected section of the aorta.
Small (3.0-4.4cm) or medium (4.5-5.4cm) aneurysms typically do not require immediate surgery but are closely monitored through regular scans.

The primary goal of treatment is to prevent an aneurysm from rupturing, as the risks associated with rupture often outweigh those of surgery.

Treatment for Large AAAs

If you have a large AAA (5.5cm or larger), you will likely be referred to a vascular surgeon, who specializes in treating blood vessel diseases. Your treatment options, based on your health and the aneurysm’s size, will be discussed.

Surgical Techniques

Endovascular Surgery
- This minimally invasive “keyhole” procedure involves making small incisions in the groin.
- A metal mesh-lined graft is guided through the leg artery to the aneurysm and sealed to the aortic wall, reinforcing the weakened area and reducing the risk of rupture.
- Advantages:
  - High success rate (98-99% make a full recovery).
  - Shorter recovery time and fewer major complications compared to open surgery.
- Disadvantages:
  - Graft attachment may be less secure, requiring regular scans to monitor for slippage or leakage, potentially necessitating further surgery.
Open Surgery
- The surgeon makes an incision in the abdomen to access and replace the enlarged section of the aorta with a synthetic graft, which is sutured into place.
- Advantages:
  - Generally more stable long-term results compared to endovascular surgery.
- Disadvantages:
  - Higher risks for individuals in poor health, with a recovery rate of 93-97%.
  - Longer recovery time and a greater risk of complications like wound or chest infections and deep vein thrombosis (DVT).

Treatment for Small or Medium AAAs

If you have a small (3.0-4.4cm) or medium (4.5-5.4cm) aneurysm, surgery may not be recommended, as the risks often outweigh the potential benefits. Instead:

Regular Monitoring: Scans every year for small aneurysms and every three months for medium aneurysms to check for growth.
Lifestyle Changes and Medications:
- Quit smoking: Smoking accelerates aneurysm growth.
- Healthy diet and regular exercise.
- Weight management.
- Blood pressure and cholesterol management: You may be prescribed medications such as ACE inhibitors for high blood pressure or statins for high cholesterol.

Treating a Ruptured AAA

Emergency treatment for a ruptured aneurysm is similar to preventive surgery, using grafts to repair the rupture. The decision to use endovascular or open surgery is made by the operating surgeon based on individual circumstances.

Preventing an Abdominal Aortic Aneurysm (AAA)

The best way to prevent the development of an abdominal aortic aneurysm (AAA), or to reduce the risk of an existing aneurysm growing and potentially rupturing, is by maintaining healthy blood vessels. Key lifestyle changes and strategies include:

1. Avoid Risk Factors

Quit smoking.
Maintain a balanced diet low in saturated fats.
Exercise regularly.
Maintain a healthy weight.

Managing High Blood Pressure and Cholesterol

If your GP identifies high blood pressure or elevated cholesterol, you may be prescribed medication to reduce these levels, which can also lower your risk of developing an AAA.

2. Smoking Cessation

Smoking is a major risk factor for aneurysms, as it contributes to atherosclerosis (hardening of the arteries) and raises blood pressure. Tobacco smoke contains substances that damage artery walls, significantly increasing the risk of aneurysm development. Research shows that:

Smokers are seven times more likely to develop an AAA compared to non-smokers.
Regularly smoking more than 20 cigarettes a day increases the risk tenfold.

For help quitting smoking, speak to your GP for a referral to an NHS Stop Smoking Service or contact resources like Quit Your Way Scotland for expert advice and support. Nicotine replacement therapies (NRTs) and additional guidance can make quitting easier.

3. Healthy Diet

A high-fat diet increases the risk of atherosclerosis. Limiting foods high in saturated fats, such as:

Biscuits, cakes, butter, sausages, and bacon.

Too much saturated fat leads to high cholesterol, which can accumulate in the artery walls. Focus on healthy eating by reducing saturated fats to maintain healthy arteries.

4. Regular Exercise

Regular physical activity helps maintain a healthy heart and blood vessels, reducing blood pressure and lowering the risk of an aneurysm. Exercise also supports weight loss, further reducing blood pressure.

Adults should aim for at least 150 minutes of moderate-intensity aerobic activity each week (e.g., cycling or brisk walking). The goal is to feel warm and slightly out of breath.
Activities can range from sports and walking to gardening.

5. Maintaining a Healthy Weight

Being overweight forces your heart to work harder, raising blood pressure and putting extra stress on your arteries. Losing even a few pounds can significantly lower blood pressure and improve overall health.

Use a BMI calculator to check if you are within a healthy weight range.

Making these changes can have a major impact on reducing your risk of developing or worsening an AAA, keeping your arteries and cardiovascular system healthy.