Arteriovenous malformations
Overview
Arteriovenous malformations (AVMs) are abnormal tangles of arteries that have abnormal connections between the arteries and veins in the brain or on the brain surface. This disrupts normal blood flow and oxygen circulation.
An arteriovenous malformation is an arteriovenous or a blood vessel abnormality. It could be said that it is like a “birthmark” in the brain.
In an arteriovenous malformation, blood flows directly from the arteries to the veins and bypass smaller blood vessels. Arteries take oxygen-rich blood from the heart to the brain; veins carry oxygen-depleted blood back to the lungs and heart.
Arteriovenous malformations disrupt this critical process by reducing the flow of oxygenated blood to tissue downstream. As a result, the downstream or surrounding tissues do not get enough oxygen. There is also a risk that these fragile vessels will tear.
Unruptured arteriovenous malformations often do not have symptoms.
Why is treatment important?
When left untreated an arteriovenous malformation can enlarge and rupture, affecting the normal blood flow to the brain. This can cause:
- A haemorrhage – bleeding into the brain
- Stroke
- Hydrocephalus – build-up of fluid in the cavities (ventricles) deep inside the brain.
The most common complications of arteriovenous malformations are bleeding and seizures. This bleeding can cause significant neurological (“brain”) damage and can even be fatal.
The principal aim of treatment is improvement in survival, quality of life, and to reach a state when a patient is free from any brain or nerve damage.
There are numerous treatment options for arteriovenous malformations (AVMs).
Treatment plans are developed to offer patients the highest chance of obliterating (blocking off abnormal blood flow) the AVM with minimal risk.
