Practice-Based Management Data of Consecutive Subjects Assessed for the Median Arcuate Ligament Syndrome at a Single Tertiary Institution

BACKGROUND The pathophysiology of median arcuate ligament syndrome (MALS) is poorly understood. The diagnostic process remains inadequately standardized, with an absence of precise criteria to guide therapeutic management. METHODS We studied consecutive subjects referred to the Department of Angiology at the University Hospital of Zurich over the past 17 years due to suspected MALS. We focused on (1) the imaging criteria that led to diagnosis, notably the results of color duplex ultrasound and the consistency with different imaging tests; (2) the clinical consequences focusing on symptom resolution. RESULTS We included 33 subjects; in 8 subjects (24.2%), the diagnosis of MALS was retained. The median expiration peak systolic velocity (PSV) on ultrasound was 3.05 (Q1; 2.1-Q3; 3.3). To confirm the sonographic results, either a CT or MRI was performed on all patients, with consistent findings confirming a significant stenosis. Seven patients underwent surgery, all involving arcuate ligament release. Four procedures were laparoscopic, one was via laparotomy, and two were robot-assisted. Additionally, two patients required angioplasty with stenting as a secondary intervention. Only two (28.6%) of the seven operated patients experienced a relief of symptoms. None experienced a relief of symptoms following secondary angioplasty, despite stent patency. The prevalence of psychiatric disorders was comparable between patients with retained and rejected diagnoses, 38% and 36%, respectively. CONCLUSIONS Our study confirmed sonography and CT/MRI consistency. However, most patients with MALS did not benefit from invasive treatment. The majority (83%) of patients without MALS were diagnosed with alternative conditions, mainly functional disorders.