Symptomatic infrarenal aortic aneurysm sac expansion 5 years post-endovascular repair without an identifiable endoleak.

A 71-year-old male presented with a symptomatic expanding 11 cm infrarenal aortic aneurysm 5 years post-endovascular aortic repair. Duplex ultrasound and angiography showed no identifiable endoleak but confirmed an enlarging aneurysm sac with a new saccular configuration. The ultrasound findings were particularly unusual in that the aneurysm sac was a mixture of hardened echogenic material and an anechoic fluid-like substance, with the echogenic material appearing to float around the sac with gravitational dependence.