Brain Vascular Tangle - Arteriovenous Malformation (AVM)

Arteriovenous Malformation (AVM) is commonly called a "brain vascular tangle" - an abnormal interconnection of arteries and veins in the brain. Normally, arterial vessels carry oxygen-rich blood to brain cells, while venous vessels return oxygen-depleted blood. When these connect directly, this vital process is disrupted.

AVMs can develop anywhere in the body but are most common in the brain and spinal cord. The exact cause remains unknown; they may be congenital or develop later in life.

People with brain AVMs may experience headaches or seizures, though the condition is often discovered incidentally during imaging for other health problems or after vessel rupture and hemorrhage.

How is a brain vascular tangle recognized?

A brain vascular tangle may not produce symptoms unless rupture occurs. Approximately half of cases present with brain hemorrhage as the first sign. Other possible symptoms include seizures, severe persistent headaches, muscle weakness, numbness, vision loss, speech difficulties, and altered consciousness. These symptoms typically appear between ages 10 and 40. Seek immediate medical attention for seizures, severe headaches, or related symptoms.

What is AVM?

In normal brain function, arteries branch into progressively smaller vessels forming capillaries where blood slows and oxygen delivery occurs. Oxygen-depleted blood then enters venous vessels returning to the heart. With AVM, arterial and venous vessels lack this supporting capillary network, causing blood to bypass surrounding tissues entirely.

Potential Risks

Brain hemorrhage: Excessive pressure may weaken vessel walls, leading to rupture and hemorrhage - a significant cause in children and young adults.

Oxygen deprivation: Blood bypassing capillaries cannot adequately oxygenate brain tissue, potentially weakening or killing brain cells.

Brain aneurysm: Weakened vessel walls may bulge outward over time, increasing rupture risk.