An arteriovenous malformation (AVM) is a rare, abnormal connection between the arteries and veins in the body. AVMs can occur anywhere in the body, but they are most commonly found in the brain, spine, or lungs. It is not known definitively what causes AVMs to grow, but there are some factors that may contribute to their growth.
Genetic Factors
AVMs are caused by mutations in the genes that control the formation and growth of the blood vessels. Some inherited genetic conditions, like hereditary hemorrhagic telangiectasia, can increase the risk of AVMs. There is also evidence that suggests that certain environmental factors may trigger the growth of an AVM.
Blood Flow
The increased pressure of the blood flow in AVMs can cause the malformation to enlarge. This is because the abnormal connection between the arteries and veins causes blood to bypass the capillaries, which can lead to an increase in the pressure in the vessels.
Tumor Growth
Tumors can also cause AVMs to grow. Tumors can cause a disruption in the normal flow of blood, which can lead to the formation of an AVM. Tumors can also cause the vessels in the area to become weak and rupture, which can lead to an AVM.
Injury
Injury to the area can also cause an AVM to grow. This is because the injury can disrupt the normal flow of blood, which can lead to an abnormal connection between the arteries and veins. This can cause the AVM to enlarge.
Medication
Certain medications, such as chemotherapy drugs, can also cause an AVM to grow. This is because these medications can cause changes in the structure of the blood vessels, which can lead to an increase in the pressure in the vessels, leading to an AVM.
It is not known exactly what causes an AVM to grow, but there are some factors that may contribute to its growth. These factors include genetics, blood flow, tumor growth, injury, and certain medications. It is important to talk to your doctor if you think that you may be at risk for an AVM.