Topic Resources
Fibromuscular dysplasia usually occurs in women aged 40 to 60 years (1). The cause is unknown. However, there may be a genetic component, and smoking may be a risk factor. Fibromuscular dysplasia overlaps clinically with certain connective tissue disorders (eg, Ehlers-Danlos syndrome type 4, cystic medial necrosis, hereditary nephritis), and neurofibromatosis) (2).
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 (in 88% of patients), carotid and intracranial arteries (25% of patients), intra-abdominal arteries (14% of patients), and upper (3% of patients) or lower (10% of patients) extremity arteries (3).
Fibromuscular dysplasia is usually asymptomatic regardless of location. Signs and symptoms, when they occur, vary by location:
Carotid arteries: Symptoms of a transient ischemic attack or stroke (typically attributed to spontaneous carotid dissection)
Intra-abdominal arteries: Symptoms of mesenteric ischemia (rare)
Intracranial arteries: Symptoms of brain aneurysm
Leg arteries: Claudication in the thighs and calves, femoral bruits, and decreased femoral pulses
Renal arteries: Renovascular hypertension
Ultrasound may suggest the diagnosis, but definitive diagnosis of fibromuscular dysplasia is made by angiography showing focal or multifocal arterial stenoses, potentially with associated aneurysm or tortuosity. Appearance may be beaded in medial or perimedial dysplasia, or a concentric band or long, smooth narrowing in other forms (2).
Screening of other vascular beds with duplex ultrasound, CT angiography, or magnetic resonance angiography is recommended when fibromuscular dysplasia is initially diagnosed (2).
Treatment of fibromuscular dysplasia varies by location. It may involve percutaneous transluminal angioplasty alone, percutaneous stent angioplasty, bypass surgery, or aneurysm repair. Smoking cessation is important. Control of other risk factors for atherosclerosis (hypertension, dyslipidemia, diabetes) helps prevent accelerated development of flow-limiting arterial stenoses.
References
1. Olin JW, Froehlich J, Gu X, et al. The United States Registry for Fibromuscular Dysplasia: results in the first 447 patients. Circulation 2012;125(25):3182-3190. doi:10.1161/CIRCULATIONAHA.112.091223
2. Gornik HL, Persu A, Adlam D, et al. First International Consensus on the diagnosis and management of fibromuscular dysplasia [published correction appears in Vasc Med 2019 Oct;24(5):475. doi: 10.1177/1358863X19865703] [published correction appears in Vasc Med 2021 Aug;26(4):NP1. doi: 10.1177/1358863X211035538]. Vasc Med 2019;24(2):164-189. doi:10.1177/1358863X18821816
3. Warchol-Celinska E, Prejbisz A, Dobrowolski P, et al. Systematic and Multidisciplinary Evaluation of Fibromuscular Dysplasia Patients Reveals High Prevalence of Previously Undetected Fibromuscular Dysplasia Lesions and Affects Clinical Decisions: The ARCADIA-POL Study. Hypertension 2020;75(4):1102-1109. doi:10.1161/HYPERTENSIONAHA.119.13239
Key Points
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.
