A pulmonary angiography is a procedure that uses a special dye (contrast material) and x-rays to see how blood flows through the lungs.
Angiography is an imaging test that uses x-rays and a special dye to see inside the arteries. Arteries are blood vessels that carry blood away from the heart.
Pulmonary arteriography; Pulmonary angiogram; Angiogram of the lungs
How the Test is Performed
This test is done in a special unit of a hospital. You will be asked to lie on an x-ray table.
Before the test starts, you will be given a mild sedative to help you relax.
An area of your body, usually the arm or groin, is cleaned and numbed with a local numbing medicine (anesthetic).
The radiologist inserts a needle or makes a small cut in a vein in the area that has been cleaned, and inserts a thin hollow tube called a catheter.
The catheter is placed through the vein and carefully moved up into and through the right-sided heart chambers and into the pulmonary artery, which leads to the lungs. The doctor can see live x-ray images of the area on a TV-like monitor, and uses them as a guide.
Once the catheter is in place, dye is injected into the catheter. X-ray images are taken to see how the dye moves through the lungs' arteries. The dye helps detect any blockages to blood flow.
Your pulse, blood pressure, and breathing are monitored during the procedure. Electrocardiogram (ECG) leads are taped to your arms and legs to monitor the electrical impulses of your heart.
After the x-rays are taken, the needle and catheter are removed.
Pressure is immediately applied to the puncture site for 20-45 minutes to stop the bleeding. After that time the area is checked and a tight bandage is applied. The leg should be kept straight for 6 hours after the procedure.
Rarely, this technique can be used to deliver medications to the lungs when a blood clot has been found.
How to Prepare for the Test
You should not eat or drink anything for 6 - 8 hours before the test.
You will be asked to wear a hospital gown and sign a consent form for the procedure. Remove jewelry from the area being imaged.
Tell your health care provider:
If you are pregnant
If you have ever had any allergic reactions to x-ray contrast material or iodine substances
If you are allergic to any medications
Which medications you are taking (including any herbal preparations)
If you have ever had any bleeding problems
How the Test Will Feel
The x-ray table is hard and cold, but you may ask for a blanket or pillow. You may feel a brief sting when the numbing medicine is given and a brief, sharp, stick as the catheter is inserted.
You may feel some pressure as the catheter moves up into the lungs. The contrast dye can cause a feeling of warmth and flushing. This is normal and usually goes away in a few seconds.
You may have some tenderness and bruising at the site of the injection after the test.
Why the Test is Performed
The test is used to detect blood clots (pulmonary embolism) and other blockages in the blood flow in the lung. Most of the time, your health care provider will already have tried other tests to diagnose a blood clot in the lungs.
Pulmonary angiography may also be used to help your doctor diagnose:
AV malformations of the lung
Congenital (present from bith) narrowing of the pulmonary vessels
Occasionally, abnormal cardiac rhythm can develop during the procedure. The doctors will monitor your heart and can treat any abnormal rhythms that develop.
Other risks include:
Allergic reaction to the contrast dye
Damage to the blood vessel as the needle and catheter are inserted
Blood clot traveling to the lungs, causing an embolism
Excessive bleeding or a blood clot where the catheter is inserted, which can reduce blood flow to the leg
Heart attack or stroke
Hematoma (a collection of blood at the site of the needle puncture)
Injury to the nerves at the puncture site
Kidney damage from the dye
There is low radiation exposure. X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. Most experts feel that the risk is low compared with the benefits.
Pregnant women and children are more sensitive to the risks of x-rays.
Jackson JE, Allison DJ, Meaney J. Angiography: Principles, techniques (including CTA and MRA) and complications. In: Grainger RC, Allison D, Dixon AK, eds. Diagnostic Radiology: A Textbook of Medical Imaging. 5th ed. New York, NY: Churchill Livingstone; 2008:chap 6.
Rubens MB, Dalal P. Pulmonary Circulation and Pulmonary Thromboembolism. In: Grainger RC, Allison D, Adam, Dixon AK, eds. Diagnostic Radiology: A Textbook of Medical Imaging. 5th ed. New York, NY: Churchill Livingstone; 2008:chap 26.
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by Shabir Bhimji, MD, PhD, Specializing in General Surgery, Cardiothoracic and Vascular Surgery, Midland, TX. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.