Median Arcuate Ligament Compression Associated with Flow-Related Visceral Aneurysms

Purpose: To identify risk factors for rupture, and to determine outcomes of endovascular treatment of median arcuate ligament (MAL) compression–related visceral artery aneurysms (VAAs). Methods and Materials: A retrospective review of patients who presented with MALC-related VAAs was performed from 1999 to 2021. A total of 21 patients (12 men) and 39 VAAs associated with MAL compression were encountered (mean age, 59 years). Imaging studies were reviewed for the number, morphology/size, and recurrence of aneurysms. Statistical analysis was performed to identify risk factors for rupture. Results: Ten patients presented with acute rupture, and 12 patients were symptomatic with nonspecific abdominal pain. Twenty-two aneurysms were fusiform in morphology and 17 aneurysms were saccular in morphology. Of the 14 aneurysms that presented with acute hemorrhage, 12 (86%) were fusiform in morphology (odds ratio, 9.0; P <.01). The mean aneurysm size was 1.3 cm, and the mean ruptured size was 0.6 cm. Thirty-one aneurysms were treated by endovascular techniques, and technical success was achieved in all cases. Fourteen patients were found to have an Arc of Buhler. No procedure-related adverse events occurred. No patient underwent surgical ligament release. The mean time of follow-up was 3.2 years, and no aneurysms recurred after endovascular treatment. Conclusions: MAL compression-associated VAAs are an important clinical entity that should be treated even at small sizes, particularly if they are fusiform in morphology. Endovascular therapy is safe and feasible and results in durable aneurysm exclusion.