What is an aneurysm?
An aneurysm is an abnormal swelling of a blood vessel. Aneurysms cause problems either by bursting causing major bleeding, or by blocking, starving the organs downstream of their blood supply.
The two commonest sites for aneurysms are the infrarenal aorta (at the back of the abdomen just below the kidneys) and the popliteal artery which is behind the knee. Aneurysms can however occur in almost any artery in the body.

