Changes in the region of the proximal aneurysm neck after endovascular repair of infrarenal aortic aneurysm.

Purpose: To analyze short and mid-term changes of the proximal aneurysm nec k and to evaluate renal function after endovascular repair of infrarenal ab dominal aortic aneurysms. Materials and methods: 24 of 29 patients, who wer e treated endoluminally with the bifurcated Vanguard Stent graft between 19 97 and 1999 underwent spiral CT follow-up after 1, 3, 6 and every 12 months . Mean follow-up period was 10.5 months (3-32 months). Follow-up included s piral CT scanning. The aortic diameter as well as cross-sectional area were measured. Stent graft position and renal perfusion were checked by spiral CT. Serum creatinine levels were determined preoperatively and during follo w-up. Results: Supra- and infrarenal aortic sizes remained stable. No corre lation to the distance between the stent-graft and the renal arteries was o bserved. Caudal migration of the stent-graft with an average of 6.5 (3-15) mm occurred in 13 patients. Cranial migration was observed in 3 patients. U ncovered stent wires partially overlapped at least one renal artery in 18 p atients. No renal infarction occurred. No significant increase of the serum creatinine level was found. Conclusion: The risk of proximal endoleakage d ue to post-interventional dilatation of the aorta abdominalis seems to be l ow. Insufficient stent graft fixation requires a wide distance between the proximal end of the stent graft and the aneurysm. In the mid-term uncovered stent wires overlapping the renal arteries had no relevant influence on re nal function.