An aortic aneurysm is a bulge in the wall of a blood vessel.
Aneurysms increase the risk of:
- Atherosclerotic plaque formation at the site of the aneurysm. This causes further weakening of the artery wall.
- A blood clot may form at the site and dislodge, increasing the chance of stroke.
- An increase in the size of the aneurysm, causing it to press on other organs. This may cause pain.
- Aneurysm rupture. Because the artery wall thins at this spot, it is fragile and may burst under stress. The rupture of an aortic aneurysm is a catastrophic, life-threatening event.
What causes aortic aneurysms?
Instead of causing a bulge in a thinned artery wall, aortic aneurysms occasionally occur between layers of the artery itself. This is called a 'dissecting aneurysm'. Blood starts to flow in the separated artery layers cutting off blood flow in the artery. This condition can rapidly lead to rupture of the artery.
Aortic aneurysms may be caused by:
- Atherosclerosis, or narrowing and hardening of the arteries, which weakens arterial walls
- Hypertension (high blood pressure)
- Local injury to the artery
- Congenital abnormality. A number of conditions, such as Marfan syndrome, are present at birth and can cause weakness of the artery walls
What are the symptoms of an aortic aneurysm?
Aortic aneurysms often cause no symptoms at all and no serious risk, unless the aortic aneurysm ruptures.
Signs of non-ruptured aortic aneurysm may include:
- Pain in the abdomen or lower back extending into the groin and legs
- An unusual pulsing or vibrating lump or sensation near the belly button
The chief sign of a ruptured aortic aneurysm is sudden, extremely severe abdominal pain, often described as a 'ripping or tearing' sensation. Other symptoms include:
- Rapid heartbeat
- Dizziness or faintness
- Difficulty breathing
- Sweating or clammy skin
- Loss of consciousness
Ruptured aortic aneurysms occur in about 1 in 10,000 people a year.
Rupture of an aneurysm can cause loss of consciousness, stroke, shock, or a heart attack.
Thoracic aortic aneurysms may cause shortness of breath, hoarseness, brassy cough (due to pressure on the lungs and airways), and difficulty swallowing (pressure on the oesophagus).
If you experience sudden unexplained chest, abdominal, or back pain, or any of these symptoms seek urgent medical attention.
How are aortic aneurysms diagnosed?
Diagnosis is difficult because often there are no symptoms. A doctor may find one incidentally during an examination. A thoracic aneurysm may cause a heart murmur. An abdominal aneurysm feels like a pulsating mass in the stomach.
If one is detected, it must be monitored. Aneurysms become dangerous and more prone to rupture when they are more than 5cm (about 2 inches) wide. Tests to detect them include: