Fibromuscular dysplasia usually occurs in women aged 40 to 60. The cause is unknown. However, there may be a genetic component, and smoking may be a risk factor. Fibromuscular dysplasia is more common among people with certain connective tissue disorders (eg, Ehlers-Danlos syndrome Ehlers-Danlos Syndromes Ehlers-Danlos syndromes are hereditary collagen disorders characterized by joint hypermobility, dermal hyperelasticity, and widespread tissue fragility. Diagnosis is clinical. Treatment is supportive... read more type 4, cystic medial necrosis, hereditary nephritis Alport Syndrome Alport syndrome is a genetically heterogeneous disorder characterized by nephritic syndrome (ie, hematuria, proteinuria, hypertension, eventual renal insufficiency) often with sensorineural... read more , neurofibromatosis Neurofibromatosis Neurofibromatosis refers to several related disorders that have overlapping clinical manifestations but that are now understood to have distinct genetic causes. It causes various types of benign... read more ).
Medial dysplasia, the most common type, is characterized by alternating regions of thick and thin fibromuscular ridges containing collagen along the media. In perimedial dysplasia, extensive collagen deposition occurs in the outer half of the media. Fibromuscular dysplasia may affect the renal arteries (60 to 75%), carotid and intracranial arteries (25 to 30%), intra-abdominal arteries (9%), or external iliac arteries (5%).
Fibromuscular dysplasia is usually asymptomatic regardless of location. Symptoms, when they occur, vary by location:
Carotid arteries: Transient ischemic attack Transient Ischemic Attack (TIA) A transient ischemic attack (TIA) is focal brain ischemia that causes sudden, transient neurologic deficits and is not accompanied by permanent brain infarction (eg, negative results on diffusion-weighted... read more or stroke Overview of Stroke Strokes are a heterogeneous group of disorders involving sudden, focal interruption of cerebral blood flow that causes neurologic deficit. Strokes can be Ischemic (80%), typically resulting... read more symptoms
Leg arteries: Claudication in the thighs and calves, femoral bruits, and decreased femoral pulses
Ultrasonography may suggest the diagnosis, but definitive diagnosis of fibromuscular dysplasia is made by angiography showing a beaded appearance (in medial or perimedial dysplasia) or a concentric band or long, smooth narrowing (in other forms).
Treatment of fibromuscular dysplasia varies by location. It may involve percutaneous transluminal angioplasty alone, percutaneous stent angioplasty, bypass surgery, or aneurysm repair. Smoking cessation Smoking Cessation Most smokers want to quit and have tried doing so with limited success. Effective interventions include cessation counseling and drug treatment, such as varenicline, bupropion, or a nicotine... read more is important. Control of other risk factors for atherosclerosis (hypertension Hypertension Hypertension is sustained elevation of resting systolic blood pressure (≥ 130 mm Hg), diastolic blood pressure (≥ 80 mm Hg), or both. Hypertension with no known cause (primary; formerly, essential... read more , dyslipidemia Dyslipidemia Dyslipidemia is elevation of plasma cholesterol, triglycerides (TGs), or both, or a low high-density lipoprotein cholesterol level that contributes to the development of atherosclerosis... read more , diabetes Diabetes Mellitus (DM) Diabetes mellitus is impaired insulin secretion and variable degrees of peripheral insulin resistance leading to hyperglycemia. Early symptoms are related to hyperglycemia and include polydipsia... read more ) helps prevent accelerated development of flow-limiting arterial stenoses.
Fibromuscular dysplasia is most common in women age 40 to 60 years.
Patients who have connective tissue disease, who smoke, or who have a family history are at higher risk.
Treatment depends on the location and includes angioplasty, bypass surgery, or aneurysm repair.