Definition

Arteriovenous malformations (AVM) are tangles of abnormal blood vessels. They can form wherever arteries and veins exist, such as the brain, spine, or lungs. The ones that form in the brain or spinal cord have the most serious symptoms.

Arteriovenous Malformation in the Brain

AVM brain blood vessels

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Causes

The exact cause of arteriovenous malformations is unknown.

Risk Factors

Risk factors that increase your chance of getting arteriovenous malformations include:

    
  • Family history—some types of arteriovenous malformations are from genetic defects that can be passed on from one generation to the next.
  • Smoking
  • Symptoms

    There are a number of symptoms that you may have if you have an arteriovenous malformation. Symptoms vary from person to person. They also depend on the location of the arteriovenous malformation in your body.

    Symptoms may include:

        
  • Seizures
  • Headache, especially on one side of the head
  • Muscle weakness
  • History of unexplained, recurrent bleeding
  • Loss of movement on one side of the body
  • Lightheadedness
  • Unable to perform movements, but not due to loss of movement
  • Loss of coordination, especially when walking
  • Sudden, severe back pain
  • Difficulty speaking or understanding language
  • Cough
  • Rapid heartbeat
  • Chest pain
  • Loss of senses
  • Visual problems
  • Memory loss
  • Difficulty thinking or mental confusion
  • Hallucinations
  • Diagnosis

    You will be asked about your symptoms and medical history. A physical exam will be done.

    Images may be taken of your bodily structures. The type of image taken will depend on the type and location of AVM you have. This can be done with:

        
  • Echocardiogram
  • Chest x-ray
  • Angiography or arteriography
  • CT scan or CAT scan
  • MRI scan
  • Magnetic resonance angiogram (MRA)
  • You may be referred to a specialist for an exam and treatment. There are a number of specialists who focus on arteriovenous malformation. The type of specialist you see will depend on the type and location of the AVM you have.

    Treatment

    The goal of treatment is to prevent hemorrhaging/bleeding. Hemorrhaging can lead to strokes, which occur due to lack of blood flow or increased pressure. Your doctor will need to determine if your arteriovenous malformation has bled, if it is not too large, and if it is in an area that can be easily reached and treated.

    Talk with your doctor about the best treatment plan for you. Treatment options include the following:

    Medication

    Medication may be taken to ease the symptoms you may be having, such as headache, back pain, and seizures. This does not remove the arteriovenous malformation.

    Surgery

    You must work with your doctor to decide whether you’d like to have surgery to treat your arteriovenous malformation. Leaving an arteriovenous malformation untreated may lead to serious complications. However, there is always a risk of nervous system damage with surgery.

    There are 3 different types of surgery available. Choosing a surgery type will depend on the size and location of the arteriovenous malformation. The types of surgery include:

    Conventional Surgery

    This standard surgery involves operating on the location where the arteriovenous malformation is located. This procedure is the most thorough treatment for arteriovenous malformations.

    Embolization

    Embolization is often used for arteriovenous malformations that are located deeper within the brain or spinal cord. Regular surgery could damage the surrounding tissue in these areas.

    A catheter will be guided through your arteries until it reaches the arteriovenous malformation. Then, a substance will be inserted to plug the fistula. This procedure does not destroy the arteriovenous malformation, but reduces the blood flow to the arteriovenous malformation and makes surgery safer.

    Radiosurgery

    This procedure uses a beam of powerful radiation. The beam is focused directly on the arteriovenous malformation. The radiation damages the walls of the blood vessels that lead to the arteriovenous malformation. This procedure does not always completely destroy the arteriovenous malformation, especially if it is large.

    Sometimes, arteriovenous malformations are best left alone based on their size and location. It is best to speak with your doctor about your decision.

    Prevention

    There is no way to prevent an arteriovenous malformation. To help reduce your chances of hemorrhaging, take the following steps:

        
  • Learn about ways to avoid high blood pressure, such as:     
  • Avoid heavy lifting.
  • Stop smoking.
  • Maintain a healthy weight.
  • Limit alcohol.
  • Eat a healthy diet that is low in sodium.
  •     
  • Avoid blood thinners, if possible.
  • Continue to see your doctor to regularly check the condition of your arteriovenous malformation.