DILATATION OF THE INFRARENAL ANEURYSM NECK AFTER ENDOVASCULAR EXCLUSION OF ABDOMINAL AORTIC-ANEURYSM

Purpose: To determine the fate of the infrarenal aneurysm neck and sup rarenal aorta after endovascular exclusion of abdominal aortic aneurys ms (AAAs). Methods: Thirty-four patients underwent endovascular AAA re pair between January 1994 and Decem ber 1995 using custom-made stent-g rafts constructed from polyester graft material and modified self-exp anding Gianturco Z-stents sutured to the graft orifices. Thirty-one pa tients were available for follow-up. Pre- and postimplantation diamete rs were measured using spiral computed tomography in the infrarenal an eurysm neck and the suprarenal aorta at the level of the superior mese nteric artery (SMA). Results: The mean follow-up time was 25 months. T here was a significant increase of the diameter of the infrarenal aneu rysm neck (+1.65 mm, p = 0.002), but not in the aorta at the level of the SMA ((+0.52 mm, p = 0.100). There was no difference in the change in diameter in the infrarenal neck in the group with a stent adjacent to the level of measurement (n = 20) compared with the group without a n adjacent stent(n = 11, p = 0.790). There was no correlation between preimplantation size of the infrarenal neck and its diameter change (r = 0.14, p = 0.488). There was no correlation (r = 0.10, p = 0.603) or association (chi-square test, p = 0.211) between aortic diameter chan ge at the level of the SMA and the infrarenal neck. Conclusions: This investigation shows a significant dilatation of the infrarenal aneurys m neck, but not in the suprarenal aorta, after endovascular AAA repair with this device. The clinical significance of these findings is uncl ear. Whether such a dilatation in the infrarenal aneurysm neck may aff ect the long-term attachment of stent-grafts remains to be shown in th e future.