The study will include patients with small AAA (diameter 4.1 to 5.4 cm defined by Computed Tomographic scan) suitable for endovascular repair (EVAR).
Randomization is designed with equal probability of assignment to each of the two groups (ie, immediate endovascular repair or surveillance group) by means of a computer-generated -random-number list . After eligibility is verified, assignment will be made using a computer database held at the Coordinating Centre.
In the immediate repair group, endovascular repair with introduction of an aortic endograft (Cook Zenith) will be performed within six weeks from randomization.
In the surveillance group, patients are followed without repair until the aneurysm reaches 5.5 cm in diameter, or enlarges at least 1.0 cm in one year, or until patient develops symptoms that are attributed to the aneurysm by the attending investigator. When one of these criteria is met, endovascular repair (if the patient remains a candidate for EVAR), or open repair will be carried out.
