Management of Inferior Mesenteric Artery Aneurysms Based on a Comprehensive Review of all Reported Cases in the Last...

Inferior mesenteric artery aneurysms (IMAAs) are rare, and their clinical behavior and management outcomes are poorly understood.

We performed a retrospective review of all published cases of IMAA from 1861 to 2025. Demographics, aneurysm size, treatment outcomes, and follow-up were analyzed.

A total of 70 studies (74 patients; 63 male, mean age 59 ± 16) report clinical details of patients with IMAA. Presentation was with abdominal pain in 18 (24%). The most common etiology was atherosclerosis in 45 patients (61%). Overall, the mean IMAA diameter was reported in 63 studies (66 cases) and was 3 ± 1.8 cm. Surgical intervention was performed in 61 patients (82%); in this group, the mean IMAA diameter was 3.3 ± 2 cm. Indication for intervention (when reported) included IMAA enlargement to over 1.5 cm in 35 (47%) or rupture in 16 (22%). Open surgery included IMA bypass/reimplantation in 29 (39%) with ligation/embolization in the rest. Early postprocedural mortality was reported in 4 patients. Median postoperative follow-up was 8 months. Late mortality was reported following repair in 1 patient at 4 years unrelated to the aneurysm (myocardial infarction). Nine (12%) patients were managed nonoperatively; the mean IMAA diameter was 2.5 ± 1.5 cm and the median reported follow-up was 6 months. With nonoperative management; 3/6 patients with IMAA size greater than 1.5 cm experienced fatal rupture between 2 and 14 weeks.

IMAAs repair should be considered at a size greater than 1.5 cm.