An arteriovenous (AV) fistula is an abnormal connection between an artery and a vein. Normally, blood flows from your arteries to your capillaries to your veins. Nutrients and oxygen in your blood travel from your capillaries to tissues in your body.
With an arteriovenous fistula, blood flows directly from an artery into a vein, bypassing some capillaries. When this happens, tissues below the bypassed capillaries receive less blood supply.
Arteriovenous fistulas usually occur in the legs, but can develop anywhere in the body. Arteriovenous fistulas are often surgically created for use in dialysis in people with severe kidney disease.
A large untreated arteriovenous fistula can lead to serious complications. If you've had an arteriovenous fistula created for dialysis, your doctors will monitor you for complications.
Small arteriovenous fistulas in your legs, arms, lungs, kidneys or brain often won't have any symptoms and usually don't need treatment other than monitoring by your doctor. Larger arteriovenous fistulas may cause symptoms.
Arteriovenous fistula symptoms may include:
An arteriovenous fistula in your lungs (pulmonary arteriovenous fistula) is a serious condition and can cause:
When to see a doctor
Causes of arteriovenous fistulas include:
Left untreated, an arteriovenous fistula can cause complications, some of which can be serious. These include:
Preparing for your appointment
If you think you may have an arteriovenous fistula, make an appointment with your family doctor. If an arteriovenous fistula is found early, your treatment may be easier and more effective. Eventually, however, you may be referred to a vascular or heart specialist (cardiologist).
Because appointments can be brief, and because there's often a lot of ground to cover, it's a good idea to be prepared for your appointment. Here's some information to help you get ready for your appointment, and know what to expect from your doctor.
What you can do
Your time with your doctor is limited, so preparing a list of questions will help you make the most of your time together. For arteriovenous fistula, some basic questions to ask your doctor include:
What to expect from your doctor
Tests and diagnosis
To diagnose an arteriovenous fistula, your doctor will use a stethoscope to listen to the blood flow through the area where he or she thinks you may have a fistula. The blood flow through an arteriovenous fistula makes a sound similar to clicking or humming machinery (machinery murmur).
If your doctor hears a machinery murmur, you'll have other tests to confirm that the murmur is caused by an arteriovenous fistula. These can include:
Treatments and drugs
It's possible your doctor may suggest only monitoring your arteriovenous fistula, especially if it's small and doesn't cause any other health problems. Some small arteriovenous fistulas close without treatment.
If your arteriovenous fistula requires treatment, your doctor may recommend:
Last Updated: 2012-04-27
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