What Are Vascular Malformations?
Vascular malformations can occur anywhere in the body, including your:
- Arms and legs
- Body cavities
- Brain and spinal cord
Arteries, capillaries, and veins
Arteries are blood vessels that travel away from the heart. They carry oxygen- and nutrient-rich blood to the body's tissues.
From arteries, blood flows into arterioles, then into capillaries.
Capillaries — blood vessels with thin walls — serve as a bridge between arteries and veins.
Veins carry oxygen- and nutrient-poor blood back to the heart and lungs.
The thin walls of the capillaries allow the body's cells to absorb oxygen and nutrients, and blood cells to pick up waste products — such as carbon dioxide — from the body's cells.
Blood that is low in oxygen travels through capillaries into venules. Venules join to form veins. Blood travels to the heart through veins.
Vascular malformation causes and complications
The exact cause of vascular malformations is unknown. They affect men and women equally.
Abnormal vessels can cause problems with the normal flow of blood by preventing enough oxygenated blood to fill the capillaries.
In some people, blood vessels form and grow in a way that causes blood to go directly from arteries to the veins without ever reaching the capillaries.
When blood does not fill capillaries, it creates a lack of oxygen and a buildup of waste in the body tissue that would normally get blood from those capillaries.
Types of vascular malformations
Doctors group vascular malformations based on their location in the body, and the type of abnormally formed blood vessel.
Vascular malformations can occur between:
- Veins only — called venous malformations.
- Lymph vessels only — called lymphatic malformations.
- Both veins and lymph vessels— called venolymphatic malformations.
- Arteries connected to veins — called arteriovenous malformations.
Doctors also categorize malformations by how much blood flows through them, including:
- High-flow — often called vascular malformations —involve abnormal connections between arteries and veins.
- Low- flow — involve abnormal connections between veins and other veins or lymph vessels.
- Mixed vascular malformations — have parts of fast high and low flow malformations. They may also become apparent following an injury, during puberty, or during pregnancy.