Vascular malformations are abnormal connections between blood vessels or lymph vessels. These malformations can occur anywhere in the body, including the brain and spinal cord.
Some vascular malformations are congenital (present at birth). Others may develop later in life due to genetic factors, injury, or surgical procedures.
These malformations can lead to pain at the location or internal bleeding. You may need surgery to correct them.
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What Is Vascular Malformation?
Vascular malformations are abnormal connections between arteries and veins. They lead to a tangled network of blood vessels.
Arteries are blood vessels that travel away from the heart. They carry oxygen- and nutrient-rich blood to the body's tissues.
From arteries, blood flows into arterioles, then into capillaries. Capillaries — blood vessels with thin walls — serve as bridges between arteries and veins.
Veins carry oxygen- and nutrient-poor blood back to the heart and lungs so it can be enriched to circulate through the arteries again.
The thin walls of the capillaries allow the body's cells to absorb oxygen and nutrients. They also allow blood cells to pick up waste products — such as carbon dioxide — from the body's cells.
Blood that is low in oxygen travels through capillaries into venules. Venules join to form veins. Blood travels to the heart through veins.
Vascular malformations can occur anywhere in the body, including your:
- Arms and legs.
- Body cavities.
- Brain and spinal cord.
- Skin.
What are the types of vascular malformations?
Doctors group vascular malformations based on their location in the body, and the type of abnormally formed blood vessel.
Vascular malformations can occur between:
- Arteries connected to veins — Called arteriovenous malformations.
- Lymph vessels only — Called lymphatic malformations.
- Veins and lymph vessels— Called venolymphatic malformations.
- Veins only — Called venous malformations.
Doctors also categorize malformations by how much blood flows through them, including:
- High-flow — Involves abnormal connections between arteries and veins. Examples include arteriovenous malformations (AVMs) and fistulas (AVFs).
- Low-flow — Involves abnormal connections between veins and other veins or lymph vessels.
- Mixed vascular malformations — Have parts of both high- and low-flow malformations. They may also become apparent following an injury, during puberty, or during pregnancy.
The two most common types of high-flow vascular malformations are:
- Arteriovenous malformations (AVMs) — These occur when oxygen-rich blood bypasses normal capillary networks and flows directly into veins. This bypass can deprive surrounding tissues of oxygen. This can lead to tissue damage or rupture and cause internal bleeding.
- Arteriovenous fistulas (AVFs) — These involve an abnormal connection between arteries and veins, often in the spinal cord. AVFs account for 70% of spinal vascular malformations. They can cause congestion, high blood pressure in veins, and reduced blood flow to critical areas.
How common are vascular malformations?
Vascular malformations are uncommon in the general population. Research shows that the annual incidence of vascular malformations is 9.85 cases per 100,000 people.
When broken down by type, each year:
- Arteriovenous malformations occur at a rate of 0.24 cases per 100,000.
- Capillary malformations occur at a rate of 2.31 cases per 100,000.
- Lymphatic malformations occur at a rate of 5.82 cases per 100,000.
- Venous malformations occur at a rate of 1.48 cases per 100,000.
This shows that while vascular malformations do occur, most individual types are relatively rare.
What causes vascular malformation?
The exact cause of vascular malformations is unknown. Potential causes may include: however they may be caused by:
- Congenital genetic mutations or hereditary conditions.
- Surgical procedures that alter blood vessel structures.
- Trauma or injury to the central nervous system.
Vascular malformation risk factors
- AVFs are more common in men and usually occur between ages 50 and 80.
- People with AVMs are usually under age 30.
Risk factors for developing vascular malformations include:
- Central nervous system injuries.
- Family history of vascular malformations.
- Genetic syndromes, such as hereditary hemorrhagic telangiectasia, Sturge-Weber syndrome, or Klippel-Trenaunay syndrome.
- Underlying genetic mutations affecting blood vessel formation.
Complications of vascular malformations
Vascular malformations can be minor or severe. Minor vascular malformations may only cause back issues and leg pain. More severe malformations can lead to acute hemorrhaging.
AVMs in the brain carry a risk of epilepsy. They can also rupture and cause internal bleeding.
What Are the Signs and Symptoms of Vascular Malformation?
The symptoms of vascular malformations vary depending on their location and type.
The most common symptoms include:
- Pain.
- Skin discoloration around the malformation.
- Swelling.
Some people with high-flow malformations can become short of breath and tire easily during activities.
The skin over a vascular malformation may be warm and discolored.
Skin could also:
- Become tender.
- Bleed.
- Bruise more easily.
- Break down.
Other symptoms of AVMs include:
- Balance and coordination problems.
- Chronic headaches.
- Muscle weakness or paralysis.
- Numbness or tingling in your limbs.
- Random episodes of pain.
- Seizures.
- Unusual sensations, such as burning or warmth.
Other symptoms of AVFs include:
- Erectile dysfunction.
- Loss of bowel and bladder control.
- Progressive weakness, particularly in the legs.
When should I see a doctor about my vascular malformation symptoms?
Seek medical attention right away if you experience any symptoms of vascular malformations. Some vascular malformations can cause life-threatening complications, like internal bleeding or nerve damage.
How Do You Diagnose Vascular Malformation?
To diagnose a vascular malformation, your provider will conduct a thorough physical exam and review your medical history.
They'll ask you about your symptoms and review your health history. They'll also likely order diagnostic imaging tests.
Tests to diagnose vascular malformation
Your doctor may order imaging tests including:
- Angiography/venography — X-rays of the blood vessels. Your doctor injects a contrast dye into your blood vessels. The dye blocks x-rays from passing through the blood dye. This enables your doctor to see your blood vessels and the vascular malformation more clearly on the x-ray.
- CT scan — Provides detailed images of blood vessels and helps detect abnormalities.
- Magnetic resonance angiography (MRA) — Identifies the precise location of the vascular malformation.
- MRI — Helps determine the exact size and extent of the malformation. This is crucial for treatment planning.
- Ultrasound — Uses sound waves to create images of the structures of your body. This test can give your doctor a picture of the vascular malformation.
How Do You Treat Vascular Malformation?
The treatment for vascular malformations depends on their severity, location, and associated symptoms. At UPMC, we work as a team to diagnose and treat vascular malformations.
Your treatment team may include:
- Dermatologists
- Interventional radiologists
- Orthopaedic specialists
- Plastic surgeons
- Vascular surgeons
We provide a range of treatment options for vascular malformations. The goal of treatment is to decrease your symptoms and the size of the malformation(s).
Compression therapy for vascular malformation
If the malformation is in an arm or leg, your doctor may recommend compression therapy. Compression therapy works by squeezing the limb to prevent the vessels from filling completely. This decreases swelling.
Embolization for vascular malformation
Endovascular embolization is a minimally invasive procedure. It permanently blocks blood flow to the malformation by injecting a glue-like substance into the affected artery.
Your doctor can perform the procedure by injecting an embolic agent such as:
- A glue-like substance called Onyx.
- A combination of liquid sclerosing agents.
- An antibiotic.
- Glue.
- Metal coils.
- Small beads.
Many vascular malformations are large. You may need more than one procedure to reduce the symptoms.
What does the doctor do during embolization?
During endovascular embolization:
- Your neurosurgeon inserts a thin tube into an artery in your leg. They guide it to the malformation using x-ray imaging.
- They inject a blocking agent (such as a medical glue or coil) to reduce blood flow to the malformation.
Endovascular embolization may occur before surgery to make surgical removal easier and safer.
Resection surgery for vascular malformation
Resection surgery involves removing the abnormal blood vessels. Although some malformations cannot be entirely removed, surgical correction can ease symptoms.
Surgery is more invasive than other treatments and usually requires more recovery time.
How effective is treatment for vascular malformation?
Treatments for vascular malformations have high success rates in managing symptoms and preventing complications. However, these procedures do not prevent new malformations from forming in the future.
Why Choose UPMC for Vascular Malformation Care?
UPMC provides expert care for vascular malformations. At UPMC, you can expect:
- Advanced care — We use advanced diagnostic tools and minimally invasive procedures. We offer the safest, most effective treatment options to improve outcomes and enhance quality of life.
- Personal care — We tailor our treatment recommendations to your needs to ensure you receive the right treatment for you.
- A team approach — We work together across medical specialties to ensure you receive the right care.
