Blood typically travels from the arteries to the capillaries to the veins. An arteriovenous fistula occurs when blood doesn’t flow through the capillaries, depriving body tissue of the oxygen and nutrients it needs.
Swollen blood vessels, or an arteriovenous fistula, develops when the blood flows straight to the veins from the arteries, skipping the capillaries altogether. The capillaries are responsible for transporting oxygen and nutrients in the blood to tissue all throughout the body. When the tissue doesn’t receive enough blood supply, serious complications can occur.
Arteriovenous fistulas are most common in the legs, but they can occur anywhere throughout the body.
Arteriovenous Fistula Symptoms
Symptoms of arteriovenous fistulas include:
- Arm or leg swelling
- Heart failure
- Low blood pressure
- Visible bulging, purplish veins just beneath the skin that look like varicose veins
If an arteriovenous fistula develops in the lungs (also known as a pulmonary arteriovenous fistula), symptoms include:
- Bluish skin
- Coughing up blood
- Deformity in the fingers
It can also develop in the gastrointestinal (GI) tract and lead to internal bleeding.
Arteriovenous Fistula Causes and Risk Factors
There are several main causes of arteriovenous fistulas:
- Cardiac catheterization. While rare, cardiac catheterization can sometimes cause arteriovenous fistulas.
- Congenital arteriovenous fistula. Experts aren’t certain of the cause, but some people are born with arteriovenous fistulas.
- Genetic conditions. Certain genetic conditions, such as Osler-Weber-Rendu disease, can increase your risk of arteriovenous fistula.
- Skin-piercing injuries. A severe injury that breaks the skin, such as a stab wound, can lead to an arteriovenous fistula.
Other risk factors include:
- Advanced age
- Being female
- High blood pressure
- High body mass index (BMI)
- Medications like blood thinners or those that control bleeding
Arteriovenous Fistula Treatments
It is important to treat arteriovenous fistula because it can lead to complications like:
- Blood clots
- Heart failure
- Leg pain
- Catheter embolization
- Ultrasound-guided compression
- Surgery for more severe cases