What are the treatment options for fibromuscular dysplasia?

Treatment Options for Fibromuscular Dysplasia

For patients with fibromuscular dysplasia (FMD), treatment should be tailored based on symptoms, affected arteries, and disease severity, with antiplatelet therapy as first-line treatment for all symptomatic patients and percutaneous angioplasty without stenting as the intervention of choice for symptomatic renal or carotid FMD.

Understanding Fibromuscular Dysplasia

FMD is a nonatherosclerotic, noninflammatory vascular disease that primarily affects medium-sized arteries, most commonly the renal and carotid arteries, but can involve almost any arterial bed. It predominantly affects women between 30-50 years of age and can manifest in various ways depending on the affected vessels.

Medical Management

Antiplatelet Therapy

• First-line therapy for all symptomatic FMD patients 1
• Administration of platelet-inhibitor medication is beneficial in patients with FMD of the carotid arteries to prevent thromboembolism 1
• Optimal drug and dosing regimen have not been definitively established, but aspirin is commonly used

Blood Pressure Control

• Essential for patients with FMD and hypertension 1
• Particularly important in renal artery FMD
• RAS blockers (ACE inhibitors or ARBs) are commonly used but require careful monitoring of renal function, especially in bilateral renal artery stenosis 1

Lifestyle Modifications

• Recommended for all patients with FMD 1
• Includes smoking cessation, regular physical activity, and healthy diet

Interventional Management

Renal Artery FMD

• Percutaneous transluminal renal angioplasty (PTRA) without stenting is the treatment of choice for hypertension due to renal FMD 1
• Indications for intervention include:
  • Resistant hypertension
  • Intolerance to antihypertensive medications
  • Progressive renal dysfunction
  • Young patients with recent onset hypertension 1
• Balloon angioplasty with bailout stent placement (if necessary) is recommended 1
• Surgical reconstruction may be considered for complex disease extending into segmental arteries or those with macroaneurysms 1

Cerebrovascular FMD

• Carotid angioplasty with or without stenting is reasonable for patients with retinal or hemispheric cerebral ischemic symptoms related to FMD of the ipsilateral carotid artery 1
• Annual noninvasive imaging of the carotid arteries is reasonable initially to detect changes in disease extent or severity 1
• For FMD-related dissection with ischemic symptoms, antiplatelet therapy is reasonable 1

Important Caveat

• Revascularization is NOT recommended for patients with asymptomatic FMD of a carotid artery, regardless of stenosis severity 1

Management Algorithm

1. Diagnosis confirmation:

   • Contrast-enhanced CTA, MRA, or catheter-based angiography 1
   • Look for the classic "string of beads" appearance in medial FMD (>80% of cases) 2

2. For all FMD patients:

   • Antiplatelet therapy (typically aspirin)
   • BP control if hypertensive
   • Annual imaging surveillance initially, less frequently once stability is confirmed 1

3. For renal artery FMD:

   • If asymptomatic: medical management only
   • If hypertensive: optimize BP control
   • If resistant hypertension or medication intolerance: consider PTRA without stenting 1

4. For cerebrovascular FMD:

   • If asymptomatic: antiplatelet therapy and surveillance
   • If symptomatic (TIA/stroke): antiplatelet therapy
   • If recurrent symptoms despite medical therapy: consider angioplasty 1
   • If dissection-related symptoms: antiplatelet therapy for 3-6 months 1

5. For FMD with aneurysms:

   • Consider covered stent or surgical repair 3, 4

Common Pitfalls to Avoid

1. Misdiagnosis: FMD is often underdiagnosed or misdiagnosed as atherosclerosis. Consider FMD in young or middle-aged women with hypertension, cervical bruits, or stroke/TIA without traditional risk factors 3.

2. Unnecessary intervention: Avoid revascularization for asymptomatic FMD, regardless of stenosis severity 1.

3. Inappropriate stenting: For renal FMD, angioplasty alone (without stenting) is typically sufficient unless complications occur 1.

4. Inadequate surveillance: FMD can progress and affect multiple vascular beds. Regular surveillance imaging is important, especially in the first few years after diagnosis 1.

5. Overlooking associated conditions: FMD patients have higher rates of aneurysms and arterial dissections that require monitoring and potential intervention 2.