Endovascular repair of a giant inferior mesenteric artery aneurysm.

Inferior mesenteric artery (IMA) aneurysms are rare visceral artery aneurysms. We present the case of a 65-year-old man with multiple comorbidities who presented with rectal bleeding and was found to have a 7 cm IMA aneurysm with an associated IMA inferior mesenteric vein arteriovenous fistula. Given the aneurysm size and rupture risk, the patient underwent successful endovascular coil embolization with complete occlusion of the aneurysm and fistula on completion angiography. This case highlights the rare coexistence of an IMA aneurysm and an IMA inferior mesenteric vein arteriovenous fistula, for which the temporal and causal relationship remains uncertain, and supports the efficacy of endovascular coil embolization in high-risk patients.