The aorta is the main blood vessel carrying blood from the heart to the rest of the body. An aortic aneurysm is an enlarged aorta, usually more than 4 cm in diameter. The wall of the aneurysmal aorta is thinned out and increases the risk that the aorta may rupture, causing life-threatening bleeding.
Common risk factors which predispose a patient to developing aortic aneurysms include:
- Coronary artery disease
- History of tobacco use and smoking
- Peripheral arterial disease
- Connective tissue disorders eg Marfan’s syndrome
Aortic aneurysms are usually asymptomatic and discovered incidentally when performing imaging of the abdomen for another reason.
Symptoms due to aortic aneurysms include back pain and abdominal pain. These symptoms are a cause of concern as it may be a sign of impending rupture and requires urgent intervention.
The common indications for intervention include:
- Aortic diameter more than 5.5cm in men and 5.0cm in women
- Symptomatic aneurysm (Back or abdominal pain)
- Rate of growth of aortic aneurysm more than 0.5cm in 6 months
- Distal embolization
1. CT scan of the aorta
- To delinate the exact anatomy of the aneurysm when planning for an intervention.
2. Duplex scan of the aorta
- For screening and follow up, a duplex scan of the aorta can be done on a 6 monthly basis.
- This is a non-invasive scan and avoids radiation exposure.
1. Open repair of the aortic aneurysm
- This requires a long abdominal incision to gain access to the aorta.
- A prosthetic tube is then sutured in place of the thinned out aorta.
- Associated with a mortality risk of around 3-5%.
- The need to clamp the aorta during the surgery places the heart under strain and may lead to heart problems after the surgery.
2. EndoVascular Aortic Repair (EVAR)
- Endovascular surgery involves placing a stent-graft inside the aneurysmal aorta to prevent continued pressurization of the aortic sac.
- The stent-graft is inserted from the femoral arteries via incisions at the groin.
- This avoids a major abdominal incision and clamping of the aorta and is associated with lower risk of mortality.