Fibromuscular dysplasia is a nonatherosclerotic, noninflammatory disease of unknown cause characterized by segmental irregularity of small and medium-sized muscular arteries. Typically, it affects white women 30-50 years of age; a family history of disease is not unusual. The most frequently involved vessels (in descending order) are the renal, carotid, and common iliac arteries. Patients present with renovascular hypertension and, less often, with renal insufficiency, transient ischemic attacks, or claudication. Angiography reveals a “string of beads” pattern of disease. There are four recognized histologic types of fibromuscular dysplasia: medial fibrodysplasia, intimal fibroplasia, medial hyperplasia, and perimedial dysplasia, though the first type is responsible for over 80% of all cases. Aspirin is advised for most patients. Percutaneous or surgical intervention is reserved for symptomatic patients.
Most lesions respond well to percutaneous angioplasty; stents do not appear to offer any advantage over angioplasty alone. More complex lesions extending into branch vessels may require interposition grafting. It is important to recognize that intracranial aneurysms are present in as many as half of patients with internal carotid fibromuscular dysplasia.
Birrer M: Treatment of renal artery fibromuscular dysplasia with balloon angioplasty: a prospective follow-up study. Eur J Vasc Endovasc Surg 2002;23:146.
Revision date: June 18, 2011
Last revised: by Dave R. Roger, M.D.