Aneurysms are enlarged arteries that occur when an artery wall weakens and the artery balloons outward. An aneurysm can burst (rupture), and lead to severe internal bleeding. Aneurysms are monitored and may be treated with medications. Severe or worsening aneurysms may require a procedure that involves inserting a graft to the artery. The graft will be a woven tube with mesh support, and it will be secured into place at the site of the aneurysm. This will support the artery walls and prevent the aneurysm from rupturing.