The Aorta is the main Artery carrying the blood from the heart to the rest of the body. In the chest (Thorax) its shape resembles a 'hockey stick', and gives branches which carry the blood to the head and neck.
The thoracic aorta extends from just above the aortic valve to the diaphragm. It is normally 2.5 cm in diameter, but it is considered aneurysmal if reaches 3.5 cm or more. Surgery is considered if it reaches 5.5 cm or more.
There are a number of factors which can lead to aneurysm formation; they include smoking, high cholesterol, high blood pressure, genetic predisposition. The condition is commonest in men.
A thoracic aneurysm is frequently without any symptoms and found by chance during investigations for other medical conditions. Some patients do experience the following symptoms however:
- Chest or upper back pain
- Persistent cough
- Hoarse voice
- Shortness of breath.
Any of the following tests can potentially diagnose a thoracic aneurysm:
- CT scan
- MRI scan
Patients with a family predisposition can also undergo genetic testing if a member of their family has been diagnosed with thoracic aneurysm.
Most people who are diagnosed with thoracic aneurysms require treatment if the aorta is bigger than 5.5 cm in diameter, and it is safe to do so. Below this size we normally recommend annual observation with CT or MRI unless symptoms occur.
Broadly speaking there are two methods of treatment:
- Open Surgery
- Endovascular stenting
We have a full discussion with the patient prior to embarking on any treatment. However, both treatments aim to prevent the aneurysm from rupturing the following can be said about each of the treatments:
During open surgery , the chest and aorta are opened and a tube made of dacron cloth is sutured to aorta. Blood will then flow through the graft instead of through the aneurysm. This has the advantage of completely replacing the diseased segment of aorta.
During endovascular stenting, the aorta is accessed via the artery at the top of the leg through a small incision and lined on the inside with a stent graft.Blood will then flow through the graft instead of through the aneurysm. This is a lesser invasive procedure with shorter recovery, but the aneurysm remains in place.