Aortic stent grafts are most commonly used to reinforce a weak spot in an artery, which is known as an aneurysm. The stent grafts are designed to seal tightly with the patient’s native artery above and below the aneurysm, and are used to treat abdominal aortic aneurysms as well as thoracic aortic aneurysms. Aortic aneurysms, as opposed to aneurysms found elsewhere in the body, are potentially very serious, as a burst aorta results in massive internal bleeding that can be fatal unless treated rapidly by an experienced emergency medical team.