An endovascular stent graft is a slender fabric tube that a physician uses to reinforce or strengthen a weak spot in a blood vessel. These devices are used to treat an abdominal aortic aneurysm, which is a bulging weakness in the aorta, the main artery that supplies blood to the stomach and legs.

In addition, stent grafts are used to correct false aneurysms, arteriovenous fistulas, and dissections. False aneurysms result from trauma and are described as sacs limited by surrounding tissue that are filled with blood. These sacs are connected with the circulation through a tear established in the artery. Arteriovenous fistulas are generated by damage of contiguous arteries and veins. Blood flows from the artery and enters the veins, which have a lower resistance to flow than the surrounding tissues. In dissection there is a separation between the layers of the artery. Blood enters into the false lumen through an entry site that is created in between the layers of the artery.

Endovascular surgery is a relatively new surgical option for people with cardiovascular disease. The term refers to a group of minimally invasive procedures that allow surgeons to treat problems in the heart or the blood vessels from within the vessels themselves by using special technologies and instruments. The procedures only require a small incision or puncture in the artery or vein; generally, this means a shorter hospital stay, a speedier recovery, and less risk of complications for the patient.

Historically, aortic aneurysms in danger of bursting were repaired by major surgery procedures. (In most cases, smaller aneurysms do not require treatment.) That meant a large abdominal incision and general anesthesia. Most patients required a hospital stay of up to 10 days to recuperate and full recovery sometimes took weeks. The risks of complications, such as bleeding, myocardial infarction, cardiac arrhythmias, and pneumonia were relatively high.

In the 1990s, surgeons began to treat aneurysms with endovascular stent grafting. Less traumatic than open surgery, the procedure was considered a breakthrough for older, frailer patients who could not have endured the rigors of traditional surgical repair. In most cases, the procedure requires only local or regional anesthesia. Most patients report less pain than in open surgery and a swifter recovery.

While promising, endovascular stent grafting of aortic aneurysm is still considered investigational by some federal health authorities. The Food and Drug Administration, however, has approved two of the devices for clinical use. A physician experienced in endovascular stenting in a well-equipped medical center should perform the procedure.