Mid-Aortic Syndrome Demonstrated by Three-Dimensional Computed Tomography: Case Report

Abstract

A 14-year-old male patient was admitted to our clinic for evaluation of systemic arterial hypertension. His right and left arm arterial blood pressures were extremely high and measured 200/120 and 180/120 mmHg, respectively. His bilateral femoral pulses were weak, and lower limb blood pressures could not be measured. By conventional echocardiography, increased left ventricular wall thickness, narrowed lumen size, and disturbed antegrade flow at the lower thoracic part of aorta were shown (Fig. 1, Movie clip 1). Three-dimensional computed tomography (CT) clearly demonstrated a long-segment severe coarctation involving the distal half of thoracic aorta (Fig. 2). The affected segment was 3 cm in length, and the intra-aortic lumen size decreased gradually to \95 % of the expected lumen size. Intrarenal part of the abdominal aorta was also narrowed, and there were no stenosis in the other branches of the aorta. Multiple aortico-aortic collaterals were also detected by CT evaluation. Cranial magnetic resonance imaging and ophthalmologic examinations were normal, and serum inflammatory markers were within the normal ranges. Thus, the patient was diagnosed with an idiopathic form of mid-aortic syndrome (MAS). Due to long-segment involvement of aorta, percutaneous transluminal angioplasty of the aorta could not be performed. We therefore planned aorta‐aortic bypass graft surgery for this patient. MAS is a rare congenital abnormality characterized by segmental narrowing of the abdominal or distal descending thoracic aorta [2‐5]. It is frequently seen with stenosis of the renal and mesenteric arteries. It can be acquired or congenital. Acquired forms are usually associated with neurofibromatosis, fibromuscular dysplasia, retroperitoneal fibrosis, Williams syndrome, mucopolysaccharidosis, and giant-cell arteritis [2, 4]. Three-dimensional CT can provide more detailed information regarding cardiovascular structures than conventional echocardiographic techniques. MAS can cause severe renovascular hypertension in children and adolescents. It is generally difficult to manage the hypertension which requires treatment with several