What is the treatment for fibromuscular dysplasia (FMD)?

Treatment for Fibromuscular Dysplasia

For renal artery FMD with hypertension or renal impairment, percutaneous transluminal angioplasty without stenting is the first-line treatment, while all patients with cranial FMD should receive antiplatelet therapy with aspirin (81-325 mg daily) regardless of symptoms. 1, 2

Medical Management

Antiplatelet Therapy

• Initiate aspirin 81-325 mg daily for all patients with cranial FMD, both symptomatic and asymptomatic 2, 3
• Continue antiplatelet therapy long-term, especially when radiographic abnormalities persist 2
• For patients with stroke/TIA attributable to dissection with FMD and no intraluminal thrombus, antiplatelet therapy is reasonable (Class IIa) 2

Blood Pressure Control

• Aggressive blood pressure control is essential for comprehensive stroke prevention in cranial FMD 2
• For renal FMD, RAS blockers (ACE inhibitors/ARBs) are the drugs of choice when percutaneous intervention is not feasible, but require careful monitoring of renal function 4
• Target optimal blood pressure management given the vascular nature of FMD 2

Lifestyle Modifications

• Implement smoking cessation and standard stroke prevention measures 2

Interventional Management

Renal Artery FMD

• Percutaneous transluminal renal angioplasty (PTRA) without stenting is the first-line revascularization technique for symptomatic renal FMD 4
• This approach achieves 100% initial success rate with long-term cumulative patency of 87% at 10 years 5
• Stenting should be reserved only for dissection or balloon angioplasty failure 4
• Open surgical revascularization is reserved for complex aneurysms, complex lesions involving arterial bifurcation or branches, or failed endovascular therapy 4

Carotid/Cranial FMD

• Carotid angioplasty with or without stenting may be reasonable for patients with recurrent ischemic stroke despite optimal medical management (Class IIb) 2
• Revascularization is NOT recommended for asymptomatic FMD regardless of stenosis severity (Class III) 2, 3
• Both surgical revascularization and endovascular approaches have been successful in alleviating ischemic symptoms in symptomatic patients 1

Surveillance and Monitoring

• Perform annual non-invasive imaging of carotid arteries initially to detect changes in disease extent or severity 3, 4
• Imaging may be repeated less frequently once stability is confirmed 3, 4
• Use contrast-enhanced CTA, MRA, or catheter-based angiography for baseline imaging 3
• Renal artery Doppler ultrasound with bilateral assessment of renal arterial resistive index is recommended for suspected renovascular hypertension 4

Systemic Evaluation

• FMD is a systemic arterial disease requiring evaluation of other vascular territories, including renal, vertebral, and iliac arteries 2, 4
• Screen for intracranial aneurysms, as they can complicate cervicocranial FMD 2
• The iliac arteries are commonly affected and require evaluation beyond the initially symptomatic site 4

Critical Pitfalls to Avoid

• Never withhold antiplatelet therapy in asymptomatic carotid FMD patients—guidelines clearly support its use 2, 3
• Never perform revascularization based solely on stenosis severity in asymptomatic patients 2, 3
• Never use anticoagulation for intracranial dissections due to increased subarachnoid hemorrhage risk 2
• Never use stenting for renal FMD as first-line therapy—angioplasty alone is preferred 1, 4
• Never fail to screen for multivascular involvement, as FMD is a systemic disease affecting multiple arterial beds 2, 4

Treatment Algorithm by Location

For Renal FMD:

1. Initiate RAS blockers for blood pressure control 4
2. If hypertension is refractory or renal function worsening, proceed to PTRA without stenting 1, 4
3. Reserve stenting only for dissection or angioplasty failure 4

For Carotid/Cranial FMD:

1. Start aspirin 81-325 mg daily immediately (symptomatic or asymptomatic) 2, 3
2. Optimize blood pressure control 2
3. Perform baseline imaging and annual surveillance initially 3
4. Consider angioplasty only if recurrent ischemic symptoms occur despite optimal medical therapy 2