THE EFFECT OF ENDOVASCULAR AORTIC STENTS PLACED ACROSS THE RENAL-ARTERIES

Objectives: To investigate renal artery patency and renal function aft er deployment of aortic stents covering the orifices of renal arteries . Design: Prospective open animal study. Setting: Department of Experi mental Surgery at a university hospital. Materials: Twenty-three pigs were used. Methods: Tell pigs were observed for 1 h after graft-anchor ing aortic stents, Gianturco (5) and Palmaz (5), were placed so that t he stents covered the renal arterial orifices. In 13 pigs, Gianturco ( 6) and Palmaz (7) stents without grafts were placed over the renal art eries and left in situ for 7 days. Renal function and blood flow were measured by renograms, iohexol clearance and ultrasonic blood pow mete r and patency was verified by angiograms. The kidneys were microscopic ally examined for signs of ischaemia and microemboli. Results: One ren al artery covered by a graft-anchoring Gianturco stent occluded. The r emaining renal arteries remained patent without any significant decrea se in venal blood flow after stent deployment. Normal renal function a nd histology was maintained. Conclusions: Aortic stents placed at the level of the renal arteries do not affect renal blood flow within 1 we ek in this experimental model. This may prove valuable in endovascular treatment of aortic aneurysms and in other procedures involving stent s.