When Blood Vessels Grow Awry Understanding Vascular Malformations

Types of vascular malformations

Several types of vascular malformations exist. Some pose little risk. But two types can be at increased risk of leaking or breaking open. This can cause bleeding in the brain, which can lead to brain damage or death. These are arteriovenous malformations, or AVMs, and cerebral cavernous malformations, or CCMs (also called cavernous angiomas).

In AVMs, arteries bypass capillaries and connect directly to veins. They’re like short circuits in your circulation. Blood then rushes into veins much faster than usual. This leads to high blood pressure in the vessels.

In CCMs, capillaries in the brain can balloon over 20 times their usual width. Blood pools in these enlarged capillaries. The walls can get stretched to the breaking point.

Both AVMs and CCMs strain blood vessel walls, increasing the chance of the vessels breaking. They can also put pressure on parts of the brain.

AVMs and CCMs are rare. Each affects less than 1% of people. Many people who have them may not know it. Most people with AVMs or CCMs have only mild symptoms, such as headaches or dizziness. They may have no symptoms at all. But once a malformation starts to leak out blood, it can cause seizures or strokes. It also becomes more likely to bleed again.

Treating vascular malformations

Vascular malformations can sometimes be removed or repaired with surgery. Doctors may also be able to use a focused beam of radiation to destroy them. Some AVMs can be plugged with a type of glue delivered through a tube inserted in an artery. But these procedures can be risky, especially if the malformation is deep inside the brain.

If a malformation has not already bled, the safest course may be to just keep an eye on it. Medications can help with some symptoms, like headaches and seizures.

“It all depends on where the malformation is in the brain, and what is the risk of treatment versus watching,” explains Dr. Issam Awad, a neurosurgeon at the University of Chicago.

Awad researches the underlying causes of vascular malformation development and bleeding. Sometimes gene abnormalities are involved. His team is looking at whether gut bacteria may play a role. They’ve shown that people with CCMs have different kinds of gut bacteria than those without CCMs. They’ve also found certain molecules in the blood that are linked with these bacteria. His team hopes that these molecules might someday be used to test whether someone will develop CCMs, or whether a CCM is likely to bleed.

Talk with your healthcare provider if you’re concerned about a family history or symptoms of a vascular malformation.

Symptoms of Vascular Malformations:

• Seizures that can involve convulsions, a loss of control over movement, or a sudden change in alertness or awareness.
• Headache, especially if it’s consistently in the same place.
• Vision problems.
• Muscle weakness in part of the body or face.
• Problems with hearing or understanding speech.
• Problems with walking or other complex movements.
• Numbness or tingling in part of the body.
• Thinking difficulties, such as confusion, memory problems, or hallucinations.
• Dizziness.
• Loss of consciousness.