Introduction
An aneurysm is a dilatation of an artery. In the femoral artery (main artery in the groin) the normal size is approximately 1 cm in diameter. If an aneurysm develops there is a risk of rupture and bleeding, clot formation and occlusion and a lack of blood flow to the leg. There are 2 types of femoral aneurysm. Some are similar to aneurysms elsewhere with a generalised dilation of the entire artery, called a true or degenerative aneurysm.
The other type is called a false aneurysm. A false aneurysm (or pseudoaneurysm) occurs when a defect or hole in the wall develops and blood flows in and out of the ‘true’ artery and is only contained by the surrounding tissues. These false aneurysms most commonly occur after trauma, including following interventional procedures that are performed through the groin, such as cardiac or peripheral stenting.
Causes
Degenerative aneurysms develop over time and similar to aneurysms elsewhere have a strong genetic tendency and can be associated with the other causes of arterial disease.
False aneurysms develop due to trauma of the arterial wall, with a tear or breach in the wall allowing ongoing blood flow through the vessel wall.
Symptoms
Most degenerative aneurysms do not cause symptoms unless they are very large. In that situation they may cause:
- Pain.
- Pulsatile lump in the groin.
- Leg swelling.
- Deep vein thrombosis (by compressing the adjacent vein).
- Clot formation.
- Embolisation of clot to the feet – discoloured and painful toes / feet.
- Lack of blood flow to the legs.
False aneurysm usually develop as a painful, pulsatile swelling of the groin. A history of trauma or medical procedures has usually occurred prior to the development of a false aneurysm. There is a risk of bleeding though the skin or into the tissues of the thigh causing extensive bruising. Urgent intervention is usually required.
Tests
Physical examination will generally confirm the presence of an enlarged artery. Ultrasound imaging (USS) is very good at assessing the size and nature of the aneurysm. CT angiography is generally used to confirm the USS and to assess options for treatment.
Diagnosis
Diagnosis is made based on the results of physical examination, ultrasound and CT imaging. The need for treatment will depend on the size and nature of the aneurysm. True aneurysms less than 3 cm in size are generally monitored with regular surveillance imaging. False aneurysms will generally require treatment, unless they are very small.
Treatment
A number of options are available for the treatment of femoral artery aneurysms.
- Thrombin injection – used to inject small, non-complicated false aneurysms.
- Covered stent – used in urgent situations where surgery is higher risk.
- Surgical repair – direct repair or replacement with a surgical graft. For most true aneurysms and larger / complicated false aneurysms.
Related Information
Popliteal Aneurysms
Peripheral Artery Disease
Arterial Bypass Surgery
Peripheral Artery Stenting