Pulmonary embolism

A pulmonary embolism is a sudden blockage in your pulmonary arteries, the blood vessels that send blood to your lungs. It usually happens when a blood clot in the deep veins in your leg breaks off and travels to your lungs.

A blood clot that travels to another part of your body is called an embolus. When an embolus blocks a blood vessel it’s called an embolism. When a pulmonary embolus blocks blood flow to your lungs, it’s called a pulmonary embolism.

You may not have any symptoms of a pulmonary embolism, depending on the size of the clot and your overall health. As blood flow becomes more and more blocked, you may experience symptoms such as:

• Coughing, including a cough that produces bloody mucus
• Dizziness
• Heart palpitations, sensations of your heart racing or pounding
• Leg pain or swelling
• Sharp and sudden chest pain
• Shortness of breath that worsens with exertion

The most common cause of a pulmonary embolism is a the breaking off of a blood clot in your leg’s deep veins, known as deep vein thrombosis (DVT). Other, rare causes of a pulmonary embolism include:

• Air bubbles
• DVT in the upper body
• Fat embolus, usually from a severely broken bone
• Tumors

You are more likely to develop blood clots if you have risk factors such as:

• Cancer
• Family history of blood clots or clotting disorders
• Heart disease
• Health history of blood clots or clotting disorders
• Long-term use of birth control pills or estrogen therapy

A pulmonary embolism is also more likely to develop after:

• Childbirth
• Heart attack or stroke
• Long plane or car rides
• Long-term bedrest
• Severe injuries, burns or fractures
• Surgery

A pulmonary embolism can be life-threatening without treatment. It can cause several complications, including:

• Cardiac arrest, when your heart suddenly stops beating
• Cardiac arrhythmia, an irregular heart rhythm
• Pleural effusion, fluid buildup in the membrane around your lungs (pleura
• Pulmonary hypertension, high blood pressure in your lungs
• Pulmonary infarction, when lung tissue dies

Rarely, people have multiple small pulmonary emboli that develop over time. This is called chronic thromboembolic pulmonary hypertension (CTEPH).

To diagnose a pulmonary embolism, your doctor does a physical exam, asks about your symptoms and orders one or more tests such as:

• Blood tests to check if you have an increased risk of blood clotting
• Chest X-rays to take pictures of your heart and lungs
• CT pulmonary angiography, using X-rays and specialized computers to create cross-sectional, 3D images of your lungs and pulmonary arteries
• Doppler ultrasound, using sound waves to look for deep vein thrombosis in your legs
• Echocardiogram to view your heart’s structures and blood vessels
• Lab tests, such as pulse oximetry to measure oxygen levels in your blood or arterial blood gas tests to measure the balance of oxygen and carbon dioxide
• Pulmonary angiogram, using a small, hollow tube (catheter) and a contrast dye to see how blood flows through the pulmonary arteries
• Ventilation-perfusion (V/Q) scan, injecting a tracer into your veins to track blood flow and compare it with air flow to check for pulmonary hypertension

Rapid treatment for pulmonary embolism is critical for good outcomes. At Penn Medicine, the Pulmonary Embolism Response Team (PERT) provides leading-edge, team-based care for acute (sudden) or chronic (long-lasting) pulmonary embolisms. We were one the of the first PERTs in the country and are among the top 10 most advanced centers in the nation in pulmonary embolism treatment.

We offer a full range of innovative treatments, including investigational therapies. Your treatment may include:

• Medications: Your doctor may prescribe drugs to dissolve the blood clot (thrombolytics) or blood thinners (anticoagulants).
• Catheter-directed therapies: A physician guides a thin tube (catheter) through a blood vessel directly to the clot in your pulmonary arteries to dissolve it with targeted medication (catheter-directed thrombolysis) or physically break up and pull the clot out (clot removal).
• Surgery: In critical cases, a surgeon may perform an emergency surgical embolectomy to physically open the artery and remove the blockage.
• Advanced life support: For patients with life-threatening heart or lung failure due to a large clot, we utilize extracorporeal membrane oxygenation (ECMO) to temporarily take over the work of the heart and lungs while treatment takes effect.
• Inferior vena cava (IVC) filter: We use a catheter to position a filter in your inferior vena cava, the main vein that carries blood from your legs to your heart. An IVC filter can help to catch emboli and prevent them from traveling to your heart or lungs.