Pulmonary arteriovenous fistula
Arteriovenous malformation - pulmonary
Pulmonary arteriovenous fistula is an abnormal connection between an artery and vein in the lungs. As a result, blood passes through the lungs without receiving enough oxygen.
Causes
Pulmonary arteriovenous fistulas are usually the result of abnormal development of the blood vessels of the lung. Most occur in people with Rendu-Osler-Weber disease (ROWD) , now commonly called hereditary hemorrhagic telangiectasia (HHT). These people often have abnormal blood vessels in many other parts of the body.
Rendu-Osler-Weber disease (ROWD)
Osler-Weber-Rendu syndrome is a disorder of the blood vessels that can cause excessive bleeding.
Fistulas also can be a complication of liver disease or lung injury, although this is much less common.
Symptoms
Many people have no symptoms. When symptoms occur, they can include:
-
Bloody sputum
Bloody sputum
Coughing up blood is the spitting up of blood or bloody mucus from the lungs and throat (respiratory tract). Hemoptysis is the medical term for cough...
-
Difficulty breathing
Difficulty breathing
Breathing difficulty may involve:Difficult breathingUncomfortable breathingFeeling like you are not getting enough air
- Difficulty exercising
- Nosebleeds
- Shortness of breath with exertion
-
Chest pain
Chest pain
Chest pain is discomfort or pain that you feel anywhere along the front of your body between your neck and upper abdomen.
-
Blue skin (
cyanosis
)
Cyanosis
Cyanosis is a bluish color to the skin or mucous membrane that is usually due to a lack of oxygen in the blood.
-
Clubbing
of the fingers
Clubbing
Clubbing is changes in the areas under and around the toenails and fingernails that occur with some disorders. The nails also show changes.
Exams and Tests
The health care provider will examine you. The exam may show:
-
Abnormal blood vessels (
telangiectasias
) on the skin or mucus membranes
Telangiectasias
Telangiectasias are small, widened blood vessels on the skin. They are usually harmless, but may be associated with several diseases.
- Abnormal sound, called a murmur when a stethoscope is placed over the abnormal blood vessel
- Low oxygen when measure with a pulse oximeter
Tests that may be done include:
-
Arterial blood gas
, with and without oxygen
Arterial blood gas
Blood gases are a measurement of how much oxygen and carbon dioxide are in your blood. They also determine the acidity (pH) of your blood.
-
Complete blood count
(CBC)
Complete blood count
A complete blood count (CBC) test measures the following:The number of red blood cells (RBC count)The number of white blood cells (WBC count)The tota...
-
Chest x-ray
Chest x-ray
A chest x-ray is an x-ray of the chest, lungs, heart, large arteries, ribs, and diaphragm.
-
Chest CT scan
Chest CT scan
A chest CT (computed tomography) scan is an imaging method that uses x-rays to create cross-sectional pictures of the chest and upper abdomen....
-
Echocardiogram
to check the function of the heart
Echocardiogram
An echocardiogram is a test that uses sound waves to create pictures of the heart. The picture and information it produces is more detailed than a s...
-
Lung function tests
Lung function tests
Pulmonary function tests are a group of tests that measure breathing and how well the lungs are functioning.
-
Perfusion radionuclide lung scan
to measure breathing and circulation (perfusion) in all areas of the lungs
Perfusion radionuclide lung scan
A pulmonary ventilation/perfusion scan involves two nuclear scan tests to measure breathing (ventilation) and circulation (perfusion) in all areas of...
-
Pulmonary
arteriogram
to view the lung arteries
Arteriogram
An arteriogram is an imaging test that uses x-rays and a special dye to see inside the arteries. It can be used to view arteries in the heart, brain...
Treatment
A small number of people who have no symptoms may not need treatment. For most people with fistulas, the treatment of choice is to block the fistula during an arteriogram (embolization).
Arteriogram
An arteriogram is an imaging test that uses x-rays and a special dye to see inside the arteries. It can be used to view arteries in the heart, brain...
Some people may need surgery to remove the abnormal vessels and nearby lung tissue.
When arteriovenous fistulas are caused by liver disease, the treatment is a liver transplant .
Liver transplant
Liver transplant is surgery to replace a diseased liver with a healthy liver.
Outlook (Prognosis)
The outlook for people with HHT is not as good as for those without HHT. For people without HHT, surgery to remove the abnormal vessels usually has a good outcome, and the condition is not likely to return.
Possible Complications
Complications may include:
-
Bleeding in the lung
Bleeding in the lung
Coughing up blood is the spitting up of blood or bloody mucus from the lungs and throat (respiratory tract). Hemoptysis is the medical term for cough...
-
Stroke
due to blood clot that travels from the lungs to the arms, legs, or brain (paradoxical venous embolism)
Stroke
A stroke occurs when blood flow to a part of the brain stops. A stroke is sometimes called a "brain attack. " If blood flow is cut off for longer th...
- Infection in the brain or heart valve, especially in patients with HHT
When to Contact a Medical Professional
Call your provider if you often have nosebleeds or difficulty breathing, especially if you also have a personal or family history of HHT.
Prevention
Because HHT is often genetic, prevention is not usually possible. Genetic counseling may help in some cases.
References
Marelli AJ. Congenital heart disease in adults. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 69.
Shovlin CL, Jackson JE. Pulmonary vascular abnormalities. In: Broaddus VC, Mason RJ, Ernst JD, et al, eds. Murray and Nadel's Textbook of Respiratory Medicine . 6th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 61.
Review Date: 8/21/2016
Reviewed By: Denis Hadjiliadis, MD, MHS, Paul F. Harron, Jr. Associate Professor of Medicine, Pulmonary, Allergy, and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.