Mid-aortic syndrome (MAS), characterized by segmental stricture of the distal thoracic and abdominal aorta, is a heterogeneous clinical syndrome with multiple etiologies.
We retrospectively analyzed 143 consecutive patients (99 females and 44 males, mean age 40.93 ± 15.31 years) with MAS seen from January 1, 2010 to January 1, 2019.
Takayasu arteritis (76.9%, 110/143) and atherosclerosis (19.6%, 28/143) were the most-common causes. There were also one patient with Behçet’s disease and one with congenital MAS in the cohort. Hypertension was the most-common manifestation. Constitutional symptoms were mainly seen in Takayasu arteritis, and neurological, gastrointestinal and vascular symptoms were common in both Takayasu arteritis and atherosclerosis. The infrarenal segment was the most-commonly involved in atherosclerosis (89.3%, 25/28), whereas lesions were more distributed in Takayasu arteritis. The mean length of involved segments was longer (43.45 ± 23.64 mm vs. 30.68 ± 12.66 mm; P = 0.018) and the degree of stenosis was lower (80.20 ± 13.36% vs. 87.50 ± 13.95%, P = 0.004) in Takayasu arteritis than atherosclerosis. The most-common concurrently involved branch was the renal artery, followed by the celiac trunk and mesenteric arteries, in both Takayasu arteritis (51.8%, 32.7% and 27.3%, respectively) and atherosclerosis (53.6%, 25.0% and 17.9%, respectively). Concurrent artery involvement and coexisting lesions were absent in MAS caused by congenial coarctation of the abdominal aorta and Behçet’s disease.
Takayasu arteritis and atherosclerosis were the most-common causes of MAS among these adults. Imaging tests provided evidence of involved segments and luminal and mural changes, aiding conclusive diagnoses and etiological differentiation of MAS.
Mid-aortic syndrome (MAS) is a rare cause of arterial hypertension, mainly presenting as high blood pressure (BP) in the upper extremities and relative hypotension distal to the lesions. It features segmental stenosis or occlusion of the distal thoracic and abdominal aorta, as well as the ostia of primary branches of the proximal abdominal aorta.
Multiple types of organ damage, including congestive heart failure, renal dysfunction and intermittent claudication of lower extremities, and even death, can be caused by uncontrolled hypertension and organ ischemia secondary to untreated MAS.
Thus, detecting and treating MAS in time is very important for organ protection and improved prognosis.
It is known that MAS is a heterogeneous clinical syndrome caused by congenital or multiple acquired etiologies.
Because it has always been reported in young patients, congenital disease, such as neurofibromatosis and Williams syndrome, was traditionally recognized as the main etiology of MAS. Recently, MAS in adults, which has not attracted enough attention, has been frequently reported. For example, abdominal aorta narrowing caused by Takayasu arteritis (TA) , and atherosclerosis (AS) has been identified in several sporadic cases, most of which included severe organ damage. Revascularization and maintenance of normal BP are considered the main treatments for MAS; however, therapeutic strategies differ significantly for different etiologies. Therefore, accurate pathogenic diagnosis is essential for providing proper, targeted treatments for patients. Nevertheless, the sporadic cases reported previously merely provided limited and unsystematic information about causes of disease constitution and the image characteristics of MAS. In this study, we report on a group of adult patients with MAS and summarize the patients’ clinical and imaging manifestations. As far as we know, this is the largest cohort of adult patients with MAS in the world.