Does a Pulmonary Embolism Appear on an X-Ray?

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Because blood clots do not show up on X-ray imaging, a chest X-ray cannot show if a pulmonary embolism is present or not. However, chest X-rays can show if certain other conditions may be causing symptoms similar to those of pulmonary embolisms and help determine if further testing is needed.

This article will look at the role of chest X-rays in diagnosing pulmonary embolism, tests used to diagnose pulmonary embolism, and symptoms of pulmonary embolism.

Doctors looking at X-rays

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Chest X-Ray Findings of Suspected Pulmonary Embolism

Pulmonary embolisms can be hard to diagnose because symptoms can be the same as other medical conditions, such as pneumonia, heart attacks, and panic attacks. When a patient presents with symptoms of pulmonary embolism, healthcare providers will do a physical exam, take a health history, and ask questions about symptoms to help decide if a patient is at risk of pulmonary embolism.

Chest X-rays are often ordered if a patient is experiencing shortness of breath or chest pain. A chest X-ray is an imaging test that gives information about the size, shape, and location of the heart, lungs, and chest arteries.

Although a chest X-ray can’t confirm if a pulmonary embolism is present or not, the images can help doctors determine the likelihood of a pulmonary embolism and if more tests are needed. For example, pulmonary embolism might be a concern if a patient’s chest X-ray is normal, but their blood oxygen level is low.

Other Medical Insights From an X-Ray

When a person has symptoms that might indicate a pulmonary embolism, a chest X-ray is ordered because it can find certain other diseases or conditions that could also be causing the symptoms. Chest X-rays can show the presence of pneumonia, fluid in the lungs, or an enlarged heart. If a chest X-ray comes back normal, the patient will likely need further testing to determine what’s causing their symptoms.

Causes of Pulmonary Embolism

The most common cause of pulmonary embolism is deep vein thrombosis (DVT), a clot that develops deep in the leg veins before breaking off and traveling to a lung artery, where it blocks blood flow. Other less common causes of pulmonary embolism are a fat embolus (a blockage caused by fat in the blood that can occur after breaking a large bone), air bubbles, or a deep vein thrombosis in the upper body.

Better Forms of Testing for Diagnosing Pulmonary Embolism

It is important to note that having multiple medical tests can be costly depending on your health insurance plan coverage and any co-pays or deductibles you may have.

Tests commonly used to diagnose pulmonary embolisms include:

Computed Tomographic Pulmonary Angiography (CT Angiogram)

This test uses a special type of X-ray that takes multiple images and uses contrast dye to make blood vessels stand out so they can be better analyzed. A CT angiogram is the most common test used to diagnose pulmonary embolism.

D-Dimer Blood Test

D-dimer is a protein the body makes when a blood clot dissolves. D-dimer levels are typically not present or very low unless the body is forming blood clots. D-dimer levels are typically high if a pulmonary embolism is present.

Ventilation-Perfusion Scan (V/Q Scan)

This test evaluates air movement in and out of the lungs (ventilation), and blood flow inside the lungs (perfusion). During the test, a small amount of a radioactive substance is administered through an intravenous infusion (IV), and multiple images are taken by a camera that detects radioactivity while the patient breathes through a tube.

Half the images show airflow, and half show blood flow in the lungs. If airflow is good, but blood flow is not, a pulmonary embolism could be the cause.

Pulmonary Angiogram

This test is typically used if V/Q scan and CT scan results are inconclusive but pulmonary embolism is still suspected. During a pulmonary angiogram, a doctor inserts a small tube, or catheter, through an incision near the groin and guides the catheter through blood vessels to the main artery carrying blood to the lungs (pulmonary artery).

Contrast dye is injected through the catheter and X-ray images are taken to see if there are any blockages as the dye travels through the blood vessels.

Pulmonary embolism affects around one in 1,000 people in the United States every year.

Other Tests That Might Be Used to Diagnose Pulmonary Embolism

Additional tests that might be used to diagnose pulmonary embolism include:

  • Blood tests: Lab tests that check arterial blood gases (oxygen and carbon dioxide levels), for genetic clotting disorders, or other blood tests may be ordered.
  • Venogram: Contrast dye is injected through a small tube in the groin and X-ray images are taken to examine blood vessels in the legs or arms to see if a blood clot in those areas might be the source of a pulmonary embolism.
  • Duplex ultrasound: This test uses ultrasound imaging to examine leg veins' blood flow and structure. Duplex imaging uses two kinds of ultrasound. One type provides images of blood vessels, and the other provides information about blood flow speed and direction.
  • Echocardiogram: This test provides ultrasound images of the heart. About 40% of people with pulmonary embolism have abnormalities on the right side of the heart. Although this test cannot diagnose a pulmonary embolism, it can tell if a pulmonary embolism is causing strain on the heart or if there are heart issues causing symptoms similar to those of a pulmonary embolism.

How to Recognize the Signs of a Pulmonary Embolism

If you are experiencing any of the signs or symptoms of pulmonary embolism, especially if they are sudden or severe, call 911 or seek emergency treatment right away. Many people with pulmonary embolism will first notice swelling and pain in a leg caused by deep vein thrombosis. When the clot travels to the lungs, there are additional symptoms that can come on quickly.

The most common symptoms of pulmonary embolism include:

  • Sudden shortness of breath
  • Sudden, sharp chest pain that's worse when coughing or taking a deep breath
  • A cough that brings up blood or pink, foamy mucus

Other symptoms of pulmonary embolism can include:

  • Feeling anxious or on edge
  • Excessive sweating
  • Feeling lightheaded, faint, or dizzy
  • Rapid breathing
  • Rapid heartbeat


A pulmonary embolism will not show up on a chest X-ray, however, an X-ray will show certain other medical conditions that cause symptoms like those of a pulmonary embolism. A chest X-ray can also help determine if more testing is necessary. If additional testing is needed, there are several tests such as CT scans and ventilation-perfusion scans that can confirm the presence of a pulmonary embolism. Symptoms of pulmonary embolism are often sudden and include shortness of breath, chest pain, and a cough that produces blood.

A Word From Verywell

If you are experiencing any symptoms of pulmonary embolism, it’s important to seek immediate medical care. Waiting too long can cause more damage to the lungs and other organs from lack of oxygen. This can lead to serious complications or death. If you’ve been diagnosed with pulmonary embolism, it’s important to work with healthcare providers to try to determine why the clot occurred and prevent further clots from occurring.

Frequently Asked Questions

  • Can you have a pulmonary embolism with a normal X-Ray?

    Yes. X-rays cannot show for certain if a pulmonary embolism is present or not. Having a normal chest X-ray does not necessarily mean that there is not a pulmonary embolism.

  • Is there a gold standard of testing for diagnosing pulmonary embolism?

    A computed tomographic pulmonary angiography, or CT angiogram, is the test most commonly used to detect pulmonary embolism. Other common tests include a ventilation-perfusion (V/Q) scan and a D-dimer blood test.

  • What do blood clots in the chest feel like?

    The most common signs of pulmonary embolism come on suddenly and include shortness of breath, chest pain, and a cough that might be bloody. If you have a blood clot in the chest you may also feel anxious, light-headed or dizzy, have rapid breathing or heartbeat, and sweat excessively.

9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Blood Clot Alliance. How is PE diagnosed?

  2. Stanford Medicine. Diagnosing pulmonary embolism (PE).

  3. Johns Hopkins Medicine. Pulmonary embolism.

  4. American Lung Association. Pulmonary embolism symptoms and diagnosis.

  5. Weitz JI, Fredenburgh JC, Eikelboom JW. A test in context: D-dimerJ Am Coll Cardiol. 2017; 70:2411. doi:10.1016/j.jacc.2017.09.024

  6. NYU Langone. Diagnosing pulmonary embolism.

  7. American Lung Association. Learn about pulmonary embolism.

  8. Stanford Medicine. Duplex ultrasound for pulmonary embolism.

  9. Stanford Medicine. Pulmonary embolism symptoms.

By Cathy Nelson
Cathy Nelson has worked as a writer and editor covering health and wellness for more than two decades. Her work has appeared in print and online in numerous outlets, including the Detroit Free Press and The Detroit News.