AVM: What are the risks?
The greatest potential risk to someone with an AVM is bleeding in the brain. Because the blood vessels in an AVM are abnormal, they may leak or rupture.
When high pressure causes an AVM to rupture, a large, rapid accumulation of blood – called a hemorrhage – can occur. About 2 to 4 percent of all AVMs each year result in hemorrhages.
Hemorrhaging from a ruptured AVM can cause stroke-like symptoms or a fatal stroke. Young people between the ages of 15 and 20 who are diagnosed with AVMs are at the highest risk of hemorrhaging.
At the Swedish Neuroscience Institute, patients with an AVM are carefully monitored for any signs that may indicate an increased risk of hemorrhage. If the hemorrhage is large, the AVM needs to be removed immediately.
After receiving treatment for AVMs, a risk of hemorrhage remains until the AVM is completely gone.