Summary of "SIR-RFS Webinar (11/19/13): Fibromuscular Dysplasia"

The webinar presented by Dr. Sharma focuses on Fibromuscular Dysplasia (FMD), a non-atherosclerotic, non-inflammatory arterial disease that primarily affects the renal and carotid arteries. The talk includes case studies, definitions, classifications, diagnostic approaches, treatment strategies, and the latest research findings related to FMD.

Key Scientific Concepts and Discoveries:

Definition of FMD: A non-atherosclerotic, non-inflammatory arterial disease that can affect various vascular beds but is most commonly seen in the carotid, renal, and external iliac arteries.
Epidemiology: FMD predominantly affects women (ratio of 9:1) and can lead to complications such as stenosis, dissections, and aneurysms.
Classification of FMD:
- Histological Classification:
  - Medial Dysplasia (75% of cases)
  - Intimal Dysplasia (less than 10%)
  - Adventitial or Periarterial Fibroplasia (1% or fewer)
- Angiographic Classification:
  - Multifocal or "String of Beads" appearance (most common)
  - Focal FMD
  - Tubular FMD
Etiology: The cause of FMD remains unclear, but there are hypotheses regarding hormonal influences, smoking, genetic associations, and renal mobility.
Clinical Manifestations: Symptoms vary based on the affected vascular bed, including hypertension, abdominal bruits, headaches, and signs of ischemia in extremities.
Diagnostic Approaches:
- Duplex Ultrasound: Initial imaging tool; increased peak systolic velocities are indicative of FMD.
- CTA/MRA: More accurate for diagnosis and confirmation of FMD.
Mimics of FMD: Conditions that may resemble FMD include atherosclerosis, vasculitis, and connective tissue diseases.
Treatment Strategies:
- Medical Therapy: Antiplatelet agents (e.g., Aspirin) are commonly used; the role of statins and ARBs is less clear.
- Vascular Therapy: Percutaneous balloon angioplasty is the standard care for symptomatic renal FMD.
- Surgical Therapy: Limited to cases with macroaneurysms.
Research Findings: The FMD patient registry has shown that the average age of diagnosis is in the late 40s to early 50s, contrary to the belief that it primarily affects younger women.

Methodology Shared:

Diagnostic Approach:
- Use Duplex Ultrasound for initial screening.
- Follow up with CTA or MRA for confirmation.
- Consider imaging of the brain for intracranial aneurysms in patients with carotid FMD.
Management Strategy:
- Antiplatelet therapy for all patients.
- Balloon angioplasty for symptomatic patients.
- Regular monitoring for progression of disease.

Researchers and Sources Featured:

Dr. Sharma (University of Virginia)
Fibromuscular Dysplasia Society of America
FMD Registry (Chair: Dr. Olen, Mount Sinai)
American Heart Association
Cleveland Clinic and various other medical institutions involved in FMD research and patient care.