Management of Fibromuscular Dysplasia (FMD)

Diagnostic Approach

• The American Heart Association recommends duplex ultrasonography as an initial screening test for FMD (Class I recommendation) 1, 2
• The American Heart Association recommends computed tomographic angiography and magnetic resonance angiography as screening tests for FMD (Class I recommendation) 1, 3
• Catheter angiography is the gold standard for diagnosing FMD and should be performed when clinical suspicion is high and noninvasive tests are inconclusive 1
• The American Heart Association does not recommend captopril renal scintigraphy, selective renal vein renin measurements, and plasma renin activity as screening tests for FMD (Class III recommendation) 1, 3

Treatment Approach

• The European Society of Cardiology recommends that all patients with FMD receive appropriate medical therapy to reduce blood pressure initially 4, 5
• The European Society of Cardiology recommends RAS blockers (ACEIs/ARBs) as the drugs of choice for FMD when percutaneous intervention is not feasible, but requires careful monitoring of renal function 4, 5
• Percutaneous transluminal renal angioplasty (PTRA) without stenting is the first-line revascularization technique for symptomatic renal FMD (Class IIa recommendation) 4, 5
• Stenting should be considered only in the management of dissection or balloon angioplasty failure 5
• Open surgical revascularization should be reserved for cases with complex aneurysms, complex lesions involving arterial bifurcation or branches, or failed endovascular therapy 5, 6

Special Considerations

• FMD is now recognized as a systemic disease affecting multiple vascular beds, requiring evaluation of other arterial territories, particularly carotid and vertebral arteries 4
• Aneurysm formation is a potential complication of FMD 3

Diagnostic Approach for Fibromuscular Dysplasia

Vascular Assessment

• The iliac arteries are commonly affected in fibromuscular dysplasia, requiring evaluation beyond the initially symptomatic site 7
• Annual non-invasive imaging of the carotid arteries is reasonable initially for patients with FMD to detect changes in disease extent or severity (Class IIa recommendation) 8
• Imaging studies may be repeated less frequently once stability has been confirmed 8

Laboratory Assessment

• Assessment of sodium intake (24-hour urinary sodium or sodium-to-creatinine ratio in morning urine) may be helpful when evaluating for renovascular hypertension 9
• Very elevated renin levels may raise suspicion for renovascular hypertension 9
• Renal artery Doppler ultrasound with bilateral assessment of renal arterial resistive index is recommended for patients with suspected renovascular hypertension due to FMD 9

Management of Fibromuscular Dysplasia

Cardiovascular Risk Considerations

• FMD patients are already at increased cardiovascular risk due to their underlying vascular disease, with 13.4% experiencing TIA, 12% experiencing cervical artery dissection, and 9.8% having had a stroke 10