Before we begin: Arteriovenous malformations (AVMs) are defects in your arteries, veins, and capillaries. They are common in the brain and spine. Find out more.
This tutorial walks you through everything you need to know about arteriovenous malformations. We explain it in plain language, step by step, so whether you are a student, a patient, or simply curious, you will come away with a solid understanding.
We cover what it is, why it matters, how it is diagnosed, and what you can do about it. Key facts are called out along the way.
What are arteriovenous malformations (AVMs)? Arteriovenous malformations (AVMs) are defects in your vascular system. Your vascular system is your body’s network of blood vessels. It includes your:
Arteries, which carry oxygen-rich blood from your heart to your tissues and organs.
Veins, which carry the blood and waste products back to your heart.
Capillaries, which are tiny blood vessels that connect your small arteries to your small veins.
An AVM is an abnormal tangle of arteries and veins. They are connected to each other, with no capillaries between them. Without the capillaries, the blood flow from the arteries goes directly into the veins at a faster rate than normal. Because of this, the nearby tissue does not get all the oxygen it would normally get. This lack of oxygen can lead to tissue damage and the death of nerve cells and other cells. The fast rate of blood flow can also increase the blood pressure inside the arteries and veins. This can weaken the arteries and veins. A weakened artery or blood vessel could burst or leak blood.
What causes arteriovenous malformations (AVMs)? AVMs are rare. The cause of AVMs is unknown. Most of the time, people are born with them. But sometimes they can appear shortly after birth or later in life.
What are the symptoms of arteriovenous malformations (AVMs)? The symptoms of AVM will depend on where the AVM is located. They can happen anywhere in the body, but they are more common in the brain or spinal cord. Most people with brain or spinal cord AVMs have few, if any, major symptoms. But if a weakened blood vessel bursts, it can spill blood into the brain (called a hemorrhage). Severe hemorrhages can cause a stroke and brain damage.
If an AVM is causing symptoms, they can include:
Seizures
Headache
Pain in the area where the AVM is located
Vision problems
Muscle weakness
Problems with movement and speech
Confusion
Dizziness
Loss of consciousness
How are arteriovenous malformations (AVMs) diagnosed? To find out if you have an AVM, your health care provider:
Will ask about your symptoms and medical history.
Will do a physical exam. This may include listening for a bruit. A bruit is whooshing sound caused by the rapid blood flow through the arteries and veins of an AVM.
May order imaging tests, such as a CT scan, MRI, ultrasound, or cerebral angiography. For a cerebral angiography, you are injected with a special dye that helps the blood vessels in your brain show up on x-rays.
What are the treatments for arteriovenous malformations (AVMs)? Treatments for AVMs will depend on factors such as:
Where the AVM is located
Its size
Your symptoms
Your overall health
Your risk of bleeding
The treatment options may include:
Monitoring for any signs that may mean you have an increased risk of hemorrhage.
Medicines to help with the symptoms from AVMs.
Surgery, which may be done if you have a higher-than-usual risk of bleeding. There are a few different types of surgery for AVMs. In some cases, you may have more than one type. Surgery can be risky, especially when it’s done on the brain or spinal cord. So you and your provider will need to discuss the risks and benefits of doing the surgery before you make a decision.
NIH: National Institute of Neurological Disorders and Stroke
Also known as: AVM.
Related topics: AVM.
Categories: Blood, Heart and Circulation, Brain and Nerves.
Source: National Institutes of Health — National Institute of Neurological Disorders and Stroke.
Key Takeaways
Understanding arteriovenous malformations is an important part of taking charge of your health. Here is what to remember:
- Know the signs — Recognizing early symptoms can lead to earlier diagnosis and better outcomes.
- Talk to your provider — If you have concerns or a family history of this condition, bring it up at your next checkup.
- Stay informed — Medical knowledge evolves. Keep learning and asking questions.
- You are not alone — Many people deal with this condition. Support groups and educational resources can help.