An aneurysm is an abnormal bulging out or ballooning of a portion of the artery, usually due to weakness of the arterial wall. The aneurysm may enlarge and rupture, often with disastrous consequences.
How Does an Aneurysm Form?
Pathophysiology and Causes of and Aneurysm
When an arterial wall is damaged or injured due to any cause, the force exerted by the blood within the artery can easily push out the weakened wall and form an aneurysm.
This may occur due to :
- Old age
- Hypertension – high blood pressure
- Atherosclerosis – hardening and narrowing of the arteries
- Vasculitis – inflammation of the blood vessels
- Untreated syphilis
- Family history
- Genetic conditions such as Marfan’s syndrome and Ehlers-Danlos syndrome.
- Trauma such as in a car accident.
- Pregnancy – linked to formation and rupture of splenic artery aneurysm
What are the Types of Aneurysm?
The aorta is the main artery which arises from the heart and passes through the thorax (chest) and abdomen to carry oxygenated blood from the heart to other parts of the body.
- Abdominal aortic aneurysm is an aneurysm occurring in the abdominal portion of the aorta. Most aortic aneurysms are abdominal aortic aneurysms.
- Thoracic aortic aneurysm occurs in the thoracic portion of the aorta and makes up the remaining cases of aortic aneurysm.
Aortic aneurysms are mostly asymptomatic (silen) and are often detected on CT scan done for some other problem.
Also known as brain aneurysm or berry aneurysm, this type of aneurysm occurs in an artery in the brain. It is usually asymptomatic unless it ruptures, where it can lead to a stroke.
These are abnormal dilatations of the peripheral arteries. The common types are “
- Popliteal aneurysm which occurs in the popliteal arteries running down the back of the thighs and knees. This comprises about 70% of peripheral aneurysms.
- Iliofemoral aneurysm which occurs in the femoral arteries in the groin and makes up 20% of peripheral aneurysms.
Aneurysms in the arteries of the arm can occur but are relatively rare.
- Carotid aneurysm – carotid arteries on either side of the neck.
- Mesenteric artery aneurysm – arteries supplying the intestine.
- Splenic artery aneurysm – artery of the spleen.
What are the Signs and Symptoms of an Aneurysm?
Symptoms may vary depending upon the site of aneurysm.
- Aortic and cerebral aneurysms are often asymptomatic but symptoms of shock such as low blood pressure and a rapid heart rate may occur when an aneurysm ruptures.
- Peripheral aneurysms usually have no symptoms either, or they may produce a throbbing mass, pain and swelling.
How is an Aneurysm Diagnosed?
Diagnosis of an Aneurysm
- CT scan
What are the Dangers of an Aneurysm?
Complications of an Aneurysm
- Rupture of an aneurysm can be dangerous and extensive bleeding can lead to death.
- Rupture of a cerebral aneurysm can result in stroke or death.
- Aortic dissection.
- Nerve compression.
- Compression of other nearby structures.
- Thromboembolism which is more common in peripheral aneurysms.
How is an Aneurysm Treated?
Treatment of an Aneurysm
Treatment will depend upon the size of aneurysm and the presence of symptoms.
- Medical treatment aims to control hypertension/hyperlipidemia, which can further weaken the site.
- Surgical treatment is necessary if the aneurysm is increasing rapidly in size and there is risk of rupture or dissection. Open surgery or endovascular repair with a stent may be done.