Mid-aortic syndrome (MAS) is one of the rarest anomalies of the vascular system and is manifested by the narrowing of the abdominal aorta and its visceral branches. In the literature, this pathology is called coarctation of the abdominal aorta or subistmic coarctation. MAS can be acquired, caused by Takayasu's or giant cell arteritis and congenital abnormalities due to abnormal development of the embryonic dorsal aorta. The characteristic features of this phenomenon are hypertension proximal to the stenotic aortic area and relative hypotension distal to it.

We present a case: a 21-year-old female patient with arterial hypertension and intermittent claudication was admitted to the Central hospital of the Ministry of Internal Affairs of the Republic of Uzbekistan.

Arterial hypertension and headaches were noticed from the age of 18, with the maximum increase in blood pressure to 280/160 mm Hg. In recent months, the distance of the intermittent claudication has decreased to 50 meters. On examination, there were no visual changes, chest pain, shortness of breath, or other neurological symptoms. BP on both arms 190/120 mm Hg, on the legs could not be determined, on Doppler 90 mm Hg. ABI - 0.47. On CT of the aorta, there are 70% stenosis of the lower part of the thoracic aorta and 85% stenosis of the interrenal aorta for about 11 cm, with hypertrophied intercostal and epigastric arteries (Fig. 1). The rest of the aorta is preserved. The patient was assigned hypotensive drugs. Lab tests show moderate proteinuria, but all inflammatory markers were within the normal references. The patient was performed Aorto - aortic bypass from the thoracic aorta to the abdominal aorta. In the early postoperative within 30 days, arterial hypertension returned to normal, intermittent claudication was solved. On the follow-up observation after 6 months of the surgery, the patient's condition was satisfactory, blood pressure was within 110/90 mm Hg, no clinical symptoms of arterial hypertension and intermittent claudication, on the CT of the abdominal aorta, compensatory enlarged intercostal arteries disappeared, the renal and visceral arteries were contrasted through the prosthesis (Fig. 2). MAS is a very rare cause of symptomatic hypertension and is characterized by narrowing of the abdominal aorta with involvement of the visceral and renal arteries and is diagnosed in childhood or adolescence. MAS may be divided into suprarenal (70%), infrarenal (7%), or intrarenal (23%) types and is usually observed in childhood or early adolescence period [1]. One of the main clinical symptoms of MAS is arterial hypertension and usually, the hypertension is refractory to hypotensive drugs. Intermittent claudication is not among the predominant clinical manifestation of MAS, but the combination of hypertension and intermittent claudication is an indication for surgery. The treatment options for MAS are medical therapy, endovascular dilatation or stenting, and open surgery. But the poor prognosis of medical therapy makes endovascular or open surgery an option of choice. We think open surgery is the main treatment for MAS such as the endovascular treatment has been shown to have little long-term success. This entails aorto-aortic bypass grafting of the affected segment or, less commonly, patch aortoplasty and usually grafting of stenotic renal and splanchnic arteries using an autovein, especially in younger patients. Without treatment and correction of the aortic lumen, most patients die until the fourth decade of their life, and the usual cause of death is myocardial infarction, heart failure, intracranial hemorrhage, and in a few cases aortic rupture [2]. In our patient main threat to her life was refractory hypertension and after surgery, our main goal was the normalization of arterial pressure.

In conclusion, the surgical treatment of MAS is an effective method for most patients and is, therefore, in spite of its complexity, the treatment of choice.

1. Chatzistamatioy E.I.M.G. , Avgeropoulou C. , Androulakis A, Tousoulis D, Kallikazaros I.E. Middle aortic syndrome: a case report and review of the literature Glob J Med Clin Case Rep, 2 (2015), pp. 13-16 2. Hubert Y. Luu, Marisa E. Pulcrano, Hong Ton Hua Surgical management of middle aortic syndrome in an adult. J Vasc Surg Cases and Innovative Techniques 2020;6:38-40.