"Tardus-parvus waveform" the only initial clue to mid-aortic syndrome- a rare cause of youth onset hypertension: A case report and a comprehensive review.

Middle aortic syndrome (MAS), an uncommon cause of secondary hypertension, is defined by obstructive narrowing of the abdominal aorta and ostia of its major branches like the renal and splanchnic arteries. Most of the cases of MAS are categorized as idiopathic; however, genetic disorders like Williams syndrome, mucopolysaccharidosis, neurofibromatosis type 1 (NF1), and Alagille syndrome, and acquired inflammatory diseases such as Takayasu arteritis and other nonspecific arteritis can also lead to MAS. MAS is commonly seen in children and young adults presenting with severe hypertension, congestive heart failure, renal failure, or severe leg claudication. The diagnosis of MAS on CT, MR, and conventional angiography is fairly straightforward. However, the spectrum of sonographic findings in MAS can be varied. Since ultrasound is frequently utilized as a first-line investigation for secondary causes of hypertension, it is especially crucial to understand the sonographic features of MAS. Here, we report a case of a young female who presented to our hospital with severe hypertension. On the Renal Doppler scan, the only clue of the renovascular etiology of her secondary hypertension was the "tardus-parvus waveform'' in the intrarenal arteries.