Teaching Case

A 35-year-old female patient presented to casualty with complaint of dyspnoea, weakness and headaches. On clinical examination, blood pressure in the lower limbs was 190/110 mm Hg with reduced pressure and weak pulsations in the bilateral upper limbs. The patient was suggested for CECT Aortography to rule out large vessel vasculitis.

A CT Aortogram was performed, covering the area from the extra-cranial neck vessels to the calf vessels and exhibited a multitude of findings. Diffuse exaggerated intimo-medial calcifications were noted in the aorta right from its root extending up to the post renal segment with relative sparing of post bifurcation segments. Calcifications with beaded lumen were noted in the branches arising from the aortic arch and abdominal aorta. Complete occlusion of both the subclavian arteries was noted with distal collateral filling bilaterally. Aneurysmal dilatation of ascending aorta was noted up to the arch. Pancardiomegaly was seen with reflux into the inferior vena cava. Diffuse long segment narrowing of inter-renal segment of abdominal aorta extending for a length of around 60mm was seen. Diffuse circumferential thickening of the wall of the abdominal aorta was noted with no obvious post contrast enhancement seen within. There was stenosis of the coeliac trunk at its origin with few collaterals distally and orificial stenosis of the right renal artery.

Mid aortic syndrome or Middle aortic syndrome (MAS) is a rare entity affecting the abdominal aorta in children and young adults. It is characterized by the narrowing of the distal thoracic and/or abdominal aorta and its branches, therefore is also known as "Abdominal aortic coarctation"[1]. MAS may be congenital or acquired post-natally. Congenital coarctation has been thought to be due to incomplete fusion or overfusion of embryonic dorsal aortas during the 4th week of gestation. Acquired MAS is associated with neurofibromatosis, William's syndrome, Alagille syndrome, fibromuscular dysplasia, retroperitoneal fibrosis (Ormond disease), mucopolysaccharidosis, foetal alcohol syndrome and giant cell arteritides including temporal (cranial) and Takayasu arteritis [1].

The severity of hypertension is the primary indication for intervention and the factor determining procedural timing. As a majority of patients with MAS are children or teenagers, the clinical benefits of early surgical intervention to reverse refractory hypertension have to be weighed against the repercussions pertaining to complications of surgery on the developing aorta. Open surgery is the primary treatment of tubular aortic narrowing (MAS) associated with renovascular hypertension and visceral artery stenosis [1]. This entails aortoaortic bypass of the diseased segment or, less often, patch aortoplasty and usually bypass grafting of the stenosed renal and visceral arteries performed with autologous conduits, particularly in the youngest of patients. Endovascular therapy may provide a sound minimally invasive treatment in MAS caused by discrete aortic stenoses that do not encompass the mesenteric and renal arteries. Hypertension is thus improved or cured in more than 70% of patients [1].

Prognosis after uncompromised surgical reconstruction is rewarding in the mid and long term in patients with congenital aortic coarctation but deteriorates in patients with aortoarteritis and recurrent inflammatory activity [1]. Our case in question had normal ESR values. Antinuclear antibody titers and anti-double stranded DNA titers were negative. Colour Doppler of the neck vessels and bilateral subclavian arteries showed normal flow. As per EULAR (European League Against Rheumatism) consensus criteria, the diagnosis of Takayasu's arteritis was confirmed as the patient had angiographic abnormalities and hypertension. The patient was managed conservatively and is being considered for surgery in near future.