A pulmonary embolism (PE) is a blockage in one of the arteries of the lungs. A saddle PE is when a large blood clot gets stuck in the main pulmonary artery.

In most cases, a blockage can happen when a blood clot breaks loose and travels to your lungs from the large veins in your legs or other parts of your body. A PE can also be caused by a tumor, fat matter, or air that gets into the lungs.

Saddle PE is a life-threatening condition that needs emergency treatment. We’ll discuss all you need to know about the causes, symptoms, and treatments for this serious condition.

Saddle PE is when a large blood clot (thrombus) gets stuck where the main pulmonary artery branches off into a Y-shape to go into each lung. The name refers to the fact that the clot “saddles” on top of both branch arteries.

Saddle PEs are rare — they make up only about 2 to 5 percent of all PE cases. If left untreated, any kind of PE is dangerous because it can block blood flow to the lungs.

A saddle PE is typically a larger and more unstable blood clot. This can increase the risk of it breaking up and causing blockages further down into the right and left pulmonary arteries, or other parts of the lungs.

The pulmonary arteries carry deoxygenated blood from the heart and to the lungs, where it’s loaded up with life-giving oxygen. If a saddle PE blocks one or more of the pulmonary arteries, this can lead to heart failure and death.

Signs and symptoms of a saddle PE are the same other types of PE. They include:

  • chest pain
  • shortness of breath
  • cough
  • blood-streaked spit from coughing
  • difficulty breathing
  • fast heart rate
  • irregular heartbeat
  • low blood pressure
  • lightheadness or dizziness
  • fever
  • clammy skin
  • blue skin
  • leg pain or swelling (if the blood clot started in the leg vein)
  • fainting

What to do if you or a loved one suspects a PE

If you or a loved one has any unexplained chest pain, difficulty breathing, or any of the other symptoms listed above, seek emergency medical treatment or call 911 immediately.

You should also get urgent medical treatment if you or a loved one has any sign of a blood clot in the leg (DVT), which can lead to a PE.

Signs and symptoms of a DVT include:

  • throbbing or cramping leg pain, usually in the calf or thigh
  • swollen veins that are hard or sore to touch
  • swelling in one leg (rarely both legs)
  • warm skin around the painful area
  • red or darkened skin around the painful area
Healthline

Saddle PE is treated in the same way that other PE cases are treated. The goal of treatment is to prevent the clot from getting bigger or new clots from forming. Treatment options include:

  • blood thinner (anticoagulant) injection
  • blood thinner oral medication
  • thrombolytics (clot-dissolving medication)
  • removing the clot via a catheter within your blood vessels

A saddle PE usually begins as a blood clot in the veins of the legs or another part of the body. The entire clot or a part of it can be carried into the lungs.

There are several causes and types of blood clots. We’ll go over a few of the common factors that can lead you to develop a saddle PE.

Health conditions

Heart and vascular diseases are some of the main risk factors PE because they affect the blood flow into the lungs.

Some of these conditions include:

Other conditions that may raise your risk of blood clots, including saddle PE, include:

You may also be at risk of getting a saddle PE, if you’ve recently had a serious injury or surgery.

Medications

Medications that are used to dissolve or break down clots in the body can lead to PE as well. This happens when a clot — or a piece of one — breaks off the wall of a blood vessel and travels to the lungs. Clot-busting drugs are called thrombolytics, and they include:

  • anistreplase (Eminase)
  • reteplase (Retavase)
  • streptokinase (Streptase)
  • tissue plasminogen activator class of drugs (Activase)

Other medications and treatments that may cause clots to form in the body include:

  • birth control pills
  • hormone therapy
  • blood transfusion
  • surgery, especially orthopedic (bone) surgeries
  • hemophilia drugs that help blood to clot
  • tamoxifen
  • thalidomide
  • cisplatin
  • vascular endothelial growth factor inhibitors (like bevacizumab)
  • tyrosine kinase receptor inhibitors (like sorafenib)
  • L-asparaginase
  • lenalidomide
  • some vitamins, minerals, and supplements

You can’t always prevent a saddle PE from happening. It can happen for no exact reason or because of an underlying condition or reason that you can’t prevent.

However, you may be able to reduce your risk of a saddle PE by keeping your risk factors for blood clots in check. Here’s a few things you can do:

  • avoid or quit smoking
  • avoid sitting or laying for long stretches of time
  • keep up with a regular exercise routine
  • wear compression stockings
  • check your blood pressure regularly
  • keep your blood sugar levels balanced

Saddle PE is treatable, but you must get urgent medical care.

The outlook for people with saddle PE is similar to those with other types of PEs. In some cases, the clot may dissolve on its own.

You may have to stay in the hospital for several days to make sure you’re in the clear. But you’ll likely have to continue treatment once you go home. Most people take blood thinner medication for at least 3 months after they have the PE.

Depending on the cause of the saddle PE, you may need additional medications, treatments, and/or lifestyle changes to prevent it from happening again.

A 2014 study found that the mortality rate for saddle PE was 3.62 percent, compared to 3.19 percent for people with other types of PE. However, the rates of other health complications were higher in people with saddle PE. These complications include:

  • heart attack or heart failure
  • shock
  • respiratory failure
  • need for further thrombolytic treatment

A saddle PE is a rare kind of PE that gets its name from its position when it gets stuck in the lungs. This clot sits within the main artery of the lungs, where it begins to branch off to either side. For this reason, a saddle PE has a high risk of blocking blood flow to the lungs.

All types of PE need urgent medical treatment. With treatment, the survival rate for a saddle PE (and other PEs) is good.

There are several causes for saddle PE. You may need ongoing treatment and lifestyle changes depending on the cause of the clot. This can help prevent a saddle PE from happening again.