Clinical Characteristics and Long-Term Outcomes of Mid-Aortic Syndrome

Abstract Objective Mid-aortic syndrome (MAS) is a rare congenital or acquired condition marked by segmental or diffuse stenosis of the distal thoracic and/or abdominal aorta and its branches. The optimal approach to medical or interventional management of MAS and long-term outcomes in adults are not well defined. We reviewed MAS cases to characterize the natural history of aortic disease, identify prognostic factors and evaluate the durability of invasive interventions. Methods We conducted a retrospective review of MAS patients who presented to Memorial Hermann Hospital and Baylor College of Medicine between 1997 and 2018. We categorized cases according to demographic and clinical manifestations, etiologies, the extent of aortic involvement, interventions and vascular outcomes. Results We identified a cohort of 13 MAS patients. The etiology of MAS was identified in 6 cases, including genetic syndromes (Neurofibromatosis Type 1 (2/13), Williams syndrome (1/13), fibromuscular dysplasia (2/13), and Takayasu arteritis (1/13)). Mean age at first documented clinical event was 25.2 (2-67) years but cases with genetic etiologies presented significantly younger (18.2 years). The most common primary anatomic site was the suprarenal and infrarenal aorta (zones 5-8). Extra-aortic locations involved the renal (4/13), celiac (3/13), and superior mesenteric (3/13) arteries. Clinical manifestations included hypertension (13/13), claudication (9/13) and postprandial abdominal pain (5/13). All patients with available follow-up data underwent at least one surgical or endovascular intervention (range: 1-8). Postoperative complications included renal failure requiring post-discharge hemodialysis and respiratory failure. There were no deaths in long-term follow-up. Conclusions MAS is a complex vasculopathy with substantial variability in clinical presentation and anatomic distribution. Extensive disease frequently requires multiple invasive interventions and results in refractory hypertension, which may predict subsequent clinical events. A multidisciplinary approach with long-term monitoring is essential for preservation of end-organ function and quality of life in this debilitating disease.