Quick Scoop

An AVM rupture is when an arteriovenous malformation, a tangle of abnormal blood vessels, breaks and bleeds. In the brain, this is a medical emergency because the bleeding can cause stroke, brain damage, or death.

What an AVM is

An AVM is an abnormal direct connection between arteries and veins that skips the usual capillaries. Because the vessels are under higher pressure than normal, they can weaken over time and rupture.

What happens when it ruptures

When a brain AVM ruptures, blood leaks into the brain tissue or surrounding spaces, causing a hemorrhage. This can lead to sudden severe headache, nausea, weakness, confusion, seizures, or loss of consciousness.

Why it matters

A rupture is serious because the first bleed can be life-threatening, and the risk of another bleed can remain high until the AVM is treated. Specialist care may involve surgery, embolization, radiosurgery, or a combination, depending on the AVM’s size and location.

If you mean a real symptom or event

If someone has sudden severe headache, seizure, fainting, weakness, or trouble speaking, call emergency services right away. AVM rupture needs urgent medical evaluation.