Long-Term Endovascular Management of a Large Superior Mesenteric Artery Aneurysm Secondary to Median Arcuate Ligament Syndrome: A Six-Year Follow-Up Study

TL;DR

A 75-year-old woman with a rare artery condition and a large aneurysm underwent multiple endovascular treatments over six years due to imaging limitations and refusal of surgery.

Contribution

This case study demonstrates long-term endovascular management of a complex SMA aneurysm in a patient with MALS and imaging constraints.

Findings

Endovascular embolization was used over six years for managing a large SMA aneurysm secondary to MALS.

Imaging limitations due to metal artifacts and embolization materials hindered precise follow-up.

The patient's refusal of surgery necessitated conservative monitoring and repeated interventions.

Abstract

Median arcuate ligament syndrome (MALS), also known as Dunbar syndrome, is a rare vascular condition caused by compression of the celiac trunk by the median arcuate ligament, leading to altered visceral blood flow and promoting collateral circulation that can predispose patients to visceral artery aneurysms (VAAs), particularly within the pancreaticoduodenal arcade. These aneurysms carry a significant risk of rupture and require timely intervention. We present the case of a 75-year-old female patient with an incidentally discovered large superior mesenteric artery (SMA) aneurysm and complete celiac trunk occlusion due to MALS. The patient’s medical history was notable for multiple comorbidities and bilateral hip arthroplasties, which rendered magnetic resonance imaging (MRI) nonviable because of pronounced metal artifacts. Over a period of six years, she underwent several staged endovascular embolization procedures using detachable coils via various arterial access points. Despite initial technical success, imaging follow-up was compromised by artifacts from orthopedic implants and embolization materials, limiting precise assessment of the aneurysm. Residual perfusion and recanalization within the aneurysm sac necessitated repeated interventions. The patient declined surgical treatment, restricting therapeutic options and prompting continued conservative monitoring. This case illustrates the complexity of managing large visceral artery aneurysms in the context of MALS and altered vascular anatomy, particularly when imaging capabilities are limited. The inability to perform MRI significantly impacted optimal follow-up and required reliance on artifact-prone options such as Doppler ultrasound and computed tomography angiography (CTA). These limitations, coupled with the patient's refusal of surgery, highlight the importance of individualized treatment approaches, multidisciplinary collaboration, and transparent patient communication regarding therapeutic options, risks, and constraints. Endovascular management of complex SMA aneurysms associated with MALS is feasible but presents significant diagnostic and therapeutic challenges. Successful outcomes in such cases depend on careful procedural planning, selection of appropriate imaging techniques, and shared decision-making tailored to patient-specific anatomical and clinical factors.

Figures