Fibromuscular Dysplasia (FMD)

What is FMD?

Fibromuscular dysplasia (FMD) is an uncommon medical condition that involves abnormal cell growth in the walls of arteries. Arteries are blood vessels that deliver blood from your heart to tissues in the rest of your body.

FMD can make your blood vessels narrow, bulge or develop a beaded appearance. It may affect:

• Carotid arteries, which are in your neck and connect your heart and brain.
• Renal arteries, which carry blood from your heart to your kidneys.
• Coronary arteries, which supply blood to your heart.
• Mesenteric arteries, which travel to your intestines.
• Other arteries, such as those that travel to your legs, arms or other parts of your body.

Who might get fibromuscular dysplasia?

Anyone can develop FMD. But the condition is much more common in women and people designated female at birth (DFAB) in more than 90% of cases, particularly those aged 40 to 70.

Other conditions may mimic fibromuscular dysplasia, including:

• Ehlers-Danlos syndrome.
• Loeys-Dietz syndrome.
• Neurofibromatosis type 1.
• Williams syndrome.
• Large vessel vasculitis.
• Atherosclerosis.
• Systemic arterial mediolysis.

How common is fibromuscular dysplasia?

Scientists aren’t sure how many people have it because in many people, it doesn’t cause symptoms or it’s discovered incidentally.

What are the types of fibromuscular dysplasia?

There are two types of FMD, based on the appearance of the arteries during diagnostic tests.

• Multifocal FMD is the most common. The arteries look like a string of beads, with a repeating pattern of bulging then narrowing.
• Focal FMD is much less common. It involves narrowed arteries or lesions on the arterial walls. A lesion is an area of abnormal tissue.

What causes fibromuscular dysplasia?

Scientists don’t know what causes FMD. Some cases have been linked to:

• Genetics, as some cases are inherited.
• Hormones.
• Injury to the artery wall like repeated stretching.
• Some factors, such as smoking, can make FMD worse.

What are the signs and symptoms of fibromuscular dysplasia?

The signs of FMD depend on the arteries affected. Some people with mild cases might not have any symptoms at all. Others might experience symptoms caused by restricted blood flow, such as:

• Bruit, an abnormal swishing noise that occurs in your neck or abdomen when a healthcare provider listens to blood flow with a stethoscope.
• Dizziness or vertigo.
• High blood pressure or uncontrolled blood pressure.
• Migraine headaches.
• Neck pain.
• Whooshing or ringing sound in the ears.

FMD can cause serious medical problems, such as:

• Aneurysm when the artery bulges and weakens (such as a brain aneurysm or abdominal artery aneurysm).
• Arterial dissection when the inside wall of the artery tears (for example, a carotid or spontaneous coronary artery dissection).
• Stroke.
• A transient ischemic attack also called a TIA or mini-stroke.

How is fibromuscular dysplasia diagnosed?

Sometimes a healthcare provider detects FMD during a routine physical examination (such as hearing a bruit). The condition also may be discovered during tests for other conditions.

If a healthcare provider suspects you have fibromuscular dysplasia, they may order the following tests:

• CT scan.
• MRI.
• Ultrasound.
• Angiography, which uses dye and X-rays to look at your arteries.

Is there a cure for fibromuscular dysplasia?

There’s no cure for FMD. Treatment focuses on relieving symptoms and preventing complications.

How is fibromuscular dysplasia treated?

Treatment for FMD varies, depending on the arteries affected, severity and symptoms. Options may include:

• Antiplatelet drugs or anticoagulant drugs to thin your blood, which can prevent clots and stroke.
• Medications for high blood pressure, such as ACE inhibitors and angiotensin receptor blockers.
• Treatments for headaches and pain, such as botulinum toxin injections (Botox®) or aspirin.
• Angioplasty, which uses a tiny balloon inserted through a catheter to open an artery.
• Surgery to repair aneurysms or create new paths for blood to travel.

How can I prevent fibromuscular dysplasia?

Because scientists don’t understand the causes of FMD, there are no strategies to prevent it.

What is fibromuscular dysplasia life expectancy?

Many people with FMD have a normal life expectancy. But rarely, an aneurysm can burst and bleed, leading to stroke, permanent nerve damage and sometimes death.

How do I take care of myself with fibromuscular dysplasia?

If you have FMD, you should take charge of your health with the following strategies:

• Check your blood pressure regularly.
• Quit smoking and using tobacco products, which make FMD worse.
• Schedule and attend all follow-up appointments, which may involve annual tests to examine the arteries.
• Take all of your medications as prescribed.

Some people with FMD find it helpful to get involved with advocacy organizations and support groups. These opportunities can connect you with other people who have the same condition. They also may help raise awareness and money for FMD research.

When should I seek medical attention with FMD?

Your healthcare provider will educate you about signs and symptoms that require immediate medical attention. This varies, depending on the arteries affected.

People with FMD should be aware of the signs and symptoms of a stroke. They include sudden:

• Confusion.
• Dizziness, loss of balance or trouble walking.
• Severe headache.
• Trouble speaking or understanding speech.
• Vision problems.
• Weakness or numbness in your face, an arm or leg (especially on just one side).

A note from Cleveland Clinic

Fibromuscular dysplasia (FMD) is an uncommon medical condition that involves abnormal cell growth in the walls of arteries. If you have signs of FMD, talk to a healthcare provider. They can offer diagnostic tests, as well as treatments to reduce symptoms and prevent complications.