Fibromuscular dysplasia of the renal arteries

Fibromuscular dysplasia is a non-atherosclerotic, noninflammatory vascular disease that primary involves medium-sized and small arteries, most commonl y the renal and carotid arteries. Dysplasic stenoses can be classified by a ngiography into three main subtypes, multifocal (multiple contiguous stenos es with the "string of beads" appearance), unifocal (single stenosis in a g iven renal artery), or tubular The multifocal subtype is the most frequent and is usually associated with medial dysplasia, whereas unifocal and tubul ar stenoses are associated with intimal and perimedial dysplasia, respectiv ely. Renovascular hypertension, mainly in women aged 30 to 50 years, is the most common manifestation of renal artery fibromuscular dysplasia. Its pre valence in hypertensive patients is estimated to less than 1 percent. The t rue prevalence of the disease is probably higher, however, because many cas es can go undetected in normotensive or asymptomatic hypertensive patients. The first line treatment is percutaneous transluminal angioplasty that usu ally allows blood pressure improvement or normalization. Stenosis progressi on is slow and rarely leads to ischemic renal failure. Recognition of renal artery fibromuscular dysplasia should lead to screening for associated car otid artery lesions. Fibromuscular dysplasia can be a familial disease.