Pulmonary (Lung) Embolism

A pulmonary embolism occurs when blood clots block one or more of the arteries to your lungs.

Pulmonary embolisms cause death in about 1 in 10 people who have them and are the leading cause of death among people in the hospital. Prompt diagnosis and treatment greatly increases a person's chances of surviving a pulmonary embolism.

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On this page

• What Is A Pulmonary Embolism?
• What Are the Symptoms of Pulmonary Embolism?
• How Do You Diagnose Pulmonary Embolism?
• How Do You Treat Pulmonary Embolism?

What Is a Pulmonary Embolism?

A pulmonary embolism occurs when blood clots form — often in the deep veins of the legs — and travel through the blood stream blocking one or more of the arteries in your lungs.

What causes pulmonary embolism?

Deep vein thrombosis (DVT) causes the type of blood clot that most frequently lodges in a lung artery. Most often DVT occurs in the legs but can also form in the arms.

What are pulmonary embolism risk factors and complications?

Risk factors for pulmonary embolism and DVT include:

• Family history of pulmonary embolism.
• Having a blood clotting disorder.
• Undergoing a major surgery.
• Prolonged inactivity, such as bed rest.
• Pancreatic, lung, breast, colon, and prostate cancers, which result in the body producing chemicals that promote clotting.
• Obesity.

Other risks include:

• Prior blood clotting episodes.
• History of heart attack or stroke.
• Smoking.
• Using birth control pills.
• Taking estrogen replacement therapy.
• Pregnancy and childbirth.
• Varicose veins.
• Advanced age.
• Fractures of the pelvis, hip, and leg.

Complications of pulmonary embolism

In patients who survive pulmonary embolism, a dangerous condition called pulmonary hypertension (high blood pressure in the lungs' arteries) can develop as a result of the blocked arteries in the lungs.

In pulmonary hypertension, the right side of the heart must pump harder than it usually does to keep enough blood flowing through the body. Over time, the heart can become enlarged to compensate. The enlarged heart eventually pumps blood more slowly and less effectively than a healthy heart and may begin to fail.

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What Are The Signs And Symptoms Of A Pulmonary Embolism?

Symptoms of pulmonary embolism include:

• Shortness of breath.
• Rapid breathing.
• Chest pain that sometimes radiates through the shoulder, arm, neck, and jaw, and can worsen with breathing.
• Blue, clammy skin.
• Coughing or spitting up blood.
• Lightheadedness.
• Fast heart rate.

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How Do You Diagnose A Pulmonary Embolism?

Your doctor may use the following tests to diagnose a pulmonary embolism:

• Computed tomography (CT) scan — x-rays take cross-sectional images of the body. A computer processes these images to create two- and three-dimensional images.
• Echocardiography (abdominal ultrasound) — uses sound waves to create images of the structure and movement of heart and blood vessels.
• V/Q lung scan (also called a ventilation and perfusion scan) — measures the flow and distribution of blood through the lungs. During this test, you breathe in a small amount of gas through a mask. The gas contains radioactive tracer. A special camera that can detect the tracer takes images. Next, your doctor injects a small amount of radioactive tracer and takes another series of images.

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How Do You Treat A Pulmonary Embolism?

Some people with pulmonary embolisms do well with blood thinners, which is the current standard of care for most patients. Others, however, experience better outcomes with more aggressive treatment and interventions aimed at dissolving the blood clot.

Medication

Anticoagulant medications, also known as blood thinners, work by preventing new blood clots in the lungs from forming and existing clots from growing larger.

You can receive these drugs as an injection, either under the skin or intravenously, or as a pill.

Anticoagulant medications may include:

• Heparin.
• Low molecular weight heparin.
• Direct thrombin inhibitors.
• Coumadin^®.

Thrombolysis

Your doctor at the UPMC Heart and Vascular Institute may recommend a more aggressive treatment that can be administered systemically though an intravenous line or via a catheter into the clot.

After inserting a catheter (a thin, flexible tube) into a blood vessel through a tiny nick in your groin or neck, your doctor will use x-ray guidance to advance the catheter to the site of the pulmonary embolism in the lung arteries and inject clot-dissolving medication directly to the pulmonary embolism.

Your doctor may also use a clot-dissolving medication to treat your pulmonary embolism.

Thrombectomy

Your surgeon will thread a catheter through your blood vessels to the site of the embolism and extract the blood clot.

Some people may need an additional procedure — called pulmonary embolectomy — to clear the clot.

Vena cava filter

To prevent further pulmonary embolisms from developing, your doctor may place a temporary vena cava filter — a small, metal device — in the vena cava, the body's largest vein.

Vena cava filters allow blood to flow through them, but prevent clots from passing into lung arteries.

Your surgeon may place them during other minimally invasive procedures, such as thrombolysis, and remove them later when the risk of pulmonary embolism decreases.

By UPMC Editorial Staff. Last reviewed on 2024-10-01.