what is an avm

An arteriovenous malformation (AVM) is an abnormal tangle of blood vessels that irregularly connects arteries and veins, disrupting blood flow and oxygen circulation. Arteries move oxygen-rich blood from the heart to the brain and other organs, while veins drain the oxygen-depleted blood back to the lungs and heart. When an AVM disrupts this critical process, the surrounding tissues might not get enough oxygen. AVMs can occur anywhere in the body but are most common in the brain and spinal cord. The cause of AVMs is not clear, but they are rarely hereditary. AVMs can cause a variety of symptoms, such as headaches, dizziness, vision problems, seizures, and changes in thinking or neurological function. AVMs can also weaken and rupture, causing bleeding in the brain, stroke, or brain damage. The diagnosis of AVMs is usually made based on imaging tests that show areas of blood flow, such as an ultrasound. Treatment options for AVMs depend on the location, size, and symptoms of the AVM, and may include surgery, radiation therapy, or embolization.