Diameter changes in isolated iliac artery aneurysms 1 to 6 years after endovascular graft repair

Objective: Precise diameter changes in iliac artery aneurysms (IAAs) after endovascular graft (EVG) repair are yet to be determined. This report describes the midterm size changes in isolated IAAs 13 to 72 months after treatment with an EVG. Methods: From January 1993 to April 1999, 31 patients with 35 true isolated IAAs (32 common iliac and 3 hypogastric) had these lesions treated with EVGs and coil embolization of the hypogastric artery or its branches. The EVG used in this study consisted of a balloon-expandable stent attached to a polytetrafluoroethylene graft. Contrast-enhanced spiral computed tomographic scans were performed at 3- to 6-month intervals to follow the aneurysms for change in diameter and endoleaks. Results: Thirty patients had a decrease in the size of their iliac aneurysms with EVG repair. All EVGs remained patent. All patients, except for one, were followed up for 13 to 72 months (mean, 31 months). The pretreatment aneurysm size ranged from 2.5 to 11.0 cm in diameter (mean, 4.6 ± 1.62 cm). After EVG treatment, the aneurysms ranged from 2.0 to 8.0 cm in diameter (mean, 3.8 ± 1.36 cm). The change in aneurysm diameter ranged from 0.5 to 3.1 cm (mean, 1.1 ± 0.62 cm) with an average change of -0.516 ± 0.01 cm/y for the first year. Five patients died of their intercurrent medical conditions during the follow-up period. One of the patients had a new endoleak and an increase in common iliac aneurysm size 18 months after EVG treatment, despite an early contrast-enhanced computed tomographic scan that showed no endoleak. This patient's aneurysm ruptured, and a standard open surgical repair was successfully performed. Another patient had a decrease in hypogastric aneurysm size after EVG treatment and no radiographic evidence of an endoleak, but eventually the aneurysm ruptured. He was successfully treated with a standard open surgical repair. Conclusions: EVGs can be an effective treatment for isolated IAAs. Properly treated with EVGs, IAAs decrease in size. The enlargement of an IAA, even if no endoleak can be detected, appears to be an ominous sign suggestive of an impending rupture. IAAs that enlarge should be closely evaluated for an endoleak. If an endoleak is detected, it should be eliminated if possible. If an endoleak cannot be found, open surgical repair should be considered.