2. Endovascular Stent Grafts
During the past decade a noninvasive but costly technique, endovascular abdominal aortic aneurysm repair, has gained some acceptance following the first Russian description of the experimental procedure in 1986. In 1991, Parodi introduced this minimally invasive percutaneous approach used to exclude blood flow through abdominal aortic aneurysms. The bypass excludes blood flow through the aneurysm which shrinks over time, and the risk of rupture is lessened. This technique involves minor surgery. A modular, bifurcated endovascular graft is introduced through an artery in the leg and is advanced to occlude and bypass the aneurysm. Since Parodi’s description, several types of endovascular grafts have been tested in Europe and the United States with the Food and Drug Administration’s (FDA) approval. The number of failures indicates the preponderance of newer types of grafts.
Endovascular graft deployment requires radiological and surgical skills. A stent graft system is introduced through the femoral artery and either self- or balloon-expanding stents are used to trap a Dacron prosthesis with the proximal end precisely below the renal artery. Some devices use hooks and barbs to secure better fixation and prevent device migration; stents in the wall facilitate fixation to the iliac artery.

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