|
Pulmonary arteriovenous fistula
Definition
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.
Alternative Names
Arteriovenous malformation - pulmonary
Causes
Pulmonary arteriovenous fistulas are usually the result of abnormal development of the blood vessels of the lung. Most occur in patients with Rendu-Osler-Weber disease (ROWD) – now commonly called hereditary hemorrhagic telangiectasia(HHT). These patients often have abnormal blood vessels in many parts of the body, including the lung.
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
- Difficulty breathing
- Difficulty exercising
- Nosebleeds
- Shortness of breath with exertion
Other possible symptoms include:
Exams and Tests
The doctor or nurse will examine you. This may show:- Abnormal blood vessels (telangiectasias) on the skin or mucus membranes
- Abnormal sound, called a murmur, when a stethoscope is placed over the abnormal blood vessel
Tests that may be done include:
- Arterial blood gas
- Complete blood count (CBC)
- Chest x-ray
- Chest CT scan
- Echocardiogram
- Liver function tests
- Perfusion radionuclide lung scan
- Pulmonary arteriogram
Treatment
A small number of patients who have no symptoms may not need treatment. For most patients with fistulas, the treatment of choice is to block the fistula during an arteriogram (embolization).
Some patients 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.
Outlook (Prognosis)
The outlook for patients with HHT is not as good as for those without HHT. For patients without HHT, surgery to remove the abnormal vessels usually has a good outcome, and the condition is not likely to return.
Possible Complications
Major complications after treatment for this condition are unusual. Complications may include:
- Bleeding in the lung
- Stroke due to blood clot that travels from the lungs to the arms, legs, or brain (paradoxical venus embolism)
- Infection in the brain or heart valve
When to Contact a Medical Professional
Call your health care provider if you often have nosebleeds or difficulty breathing, especially if you also have a personal or family history of HHT.
Prevention
Because this condition is often genetic, prevention is not usually possible.
References
Marelli AJ. Congenital heart disease in adults. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 69.
Shovlin CL, Jackson JE. Pulmonary arteriovenous malformations and other vascular abnormalities. In: Mason RJ, Broaddus CV, Martin TR, et al, eds. Textbook of Respiratory Medicine. 5th ed. Philadelphia,Pa: Saunders Elsevier; 2010: chap 54.
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Denis Hadijiliadis, MD, Assistant Professor of Medicine, Division of Pulmonary, Allergy and Critical Care, University of Pennsylvania, Philadelphia, PA. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
