Venous thromboembolism (VTE) is a life-threatening circulation problem. It’s a combination of two conditions, deep vein thrombosis (DVT) and pulmonary embolism (PE). When a blood clot forms in a deep vein, usually the leg, it’s called DVT. If that clot breaks free and moves up and into the lungs, it’s called a PE.

VTE, especially the type that develops during an extended hospital stay, is usually preventable. An early diagnosis of VTE can often be treated.

If you’ve had one VTE, there is a chance of recurrent venous thromboembolism, or the formation of a new clot that travels to the lungs.

VTE is a common problem. An estimated 10 million people around the world are diagnosed with VTE every year. Learning more about symptoms and treatment of this potentially fatal condition is important, especially if you’re at high risk.

The symptoms of recurrent venous thromboembolism are the same as the symptoms you will experience the first time you have a VTE. That means you are more likely to understand what is happening and seek immediate help.

Pain and swelling in the affected area are common symptoms of a clot. You may also notice that the skin in that area feels warm. It may be tender to the touch.

If a clot has moved to the lungs, one of the first symptoms you’ll notice is difficulty breathing. Sometimes, though, the problem is rapid breathing that you can’t slow down. Chest pain and lightheadedness are also common complaints.

A blood clot can form in a deep vein when circulation is disrupted, or there is damage to your blood vessels. Veins carry blood from the lungs and the entire body to the heart. Arteries carry blood from the heart to the lungs and the rest of the body.

If the venous circulation is poor in your legs, blood can pool and form a clot. This can restrict blood flow in a vein, which can cause DVT. If the arterial circulation is poor, it can cause a heart attack if it affects the coronary arteries. It can cause gangrene if it affects the arteries to the lower extremities.

The following may cause both VTE and recurrent VTE:

  • pregnancy
  • surgery, especially total knee or hip arthroplasty
  • use of birth control
  • inflammatory bowel disease, such as Crohn’s disease or ulcerative colitis
  • prolonged sitting, such as on an airplane
  • being bedridden
  • genetic conditions, such as protein S deficiency or factor V Leiden mutation
  • smoking
  • excessive alcohol consumption
  • obesity

If you’ve had VTE and the causes aren’t resolved, you are at risk for recurrent VTE.

A history of DVT or PE puts you at risk for recurrent VTE. According to a 2007 study, up to 25 percent of people who have had a DVT or PE will have recurrent VTE within the five years of their initial diagnosis.

A major risk factor for recurrent VTE is stopping blood-thinning medications after your first VTE is diagnosed. Blood thinners called anticoagulants help prevent blood clots from forming. Once you stop taking anticoagulants, you face higher odds of VTE recurring.

Other risk factors for recurrent VTE include:

  • thrombophilia, a condition that makes the blood more prone to clotting
  • increased age
  • being male

If you experience pain or swelling in your legs or anywhere in your body that has no obvious cause, such as a sprain or bruise, see a doctor.

If you ever have breathing difficulties, see a doctor immediately. If it’s not VTE it could be any of several serious health problems, including a heart attack or a major respiratory problem.

If you show signs of a PE or a DVT, you may be given what is called a “D-dimer” blood test. To do the test, your doctor will draw a small amount of blood, just as they would with any blood test. They will then send your blood to a lab to test. Your doctor can tell from the test results whether a blood clot is present. The test won’t reveal the clot’s location, however.

A positive D-dimer test can also occur if you’re pregnant, if you have high cholesterol, or if you have heart or liver disease. That’s why a physical exam is also necessary.

An ultrasound test can also help diagnose a blood clot in the legs. A chest X-ray and other imaging tests may also help identify the location of a blood clot that has reached the lungs.

Once VTE has been diagnosed, treatment will depend on how life-threatening the condition is and what symptoms you’re experiencing.

Anticoagulant medications are usually given immediately to help break up the clot and prevent recurrence. These may include:

  • heparin
  • fondaparinux (Arixtra)
  • warfarin (Coumadin)
  • apixaban (Eliquis)
  • rivaroxaban (Xarelto)
  • dagrigatran (Pradaxa)

A drug called a tissue plasminogen activator (tPA) can sometimes be injected to help break up clots, too.

You may also be advised to wear compression stockings, which help blood circulate in the legs, or inflatable cuffs around your arms or trunk. These also help improve blood flow.

If a dangerous blood clot is in a blood vessel in the lungs, it may need to be removed if medications or compression therapy aren’t effective. A complicated surgical procedure called pulmonary thromboendarterectomy (PTE) removes clots from the larger blood vessels in the lungs. If surgery is not an option, a catheter procedure may be helpful in clearing any blockage in a lung vein or artery.

If you have a history of VTE, you may need to be on anticoagulants for the rest of your life to reduce your chances for recurrent VTE.

If you make other smart decisions for your cardiovascular health, your outlook after VTE should be bright. This means no smoking, plenty of exercise every day, weight loss (if you’re overweight or obese), and adhering to all your medications and your doctor’s advice.

VTE can be a fatal condition, but that’s usually because it is diagnosed too late. If you are very frail or have other health problems, such as heart disease or pulmonary hypertension, VTE can also be quite serious. Pulmonary hypertension is when there is excessive force inside the blood vessels in a person’s lungs.

If you respond to symptoms promptly and seek out medical attention right away, you are more likely to have a better outlook. Contact your doctor right away if you suspect you have a blood clot.

Preventing VTE or recurrent VTE isn’t always possible. Preventive measures can be effective in some situations.

Nearly 60 percent of VTE cases develop during or right after a long hospital stay. Your healthcare providers may put you on anticoagulants, place compression stockings on you, and exercise your legs whenever possible if you are in the hospital for surgery or an extended stay. If you’re concerned about the risk of a blood clot forming, talk with your doctor about what steps they’ll take in the hospital to lower your risks.

If you’re at home, but laid up in bed, you should also ask your doctor about what you can do to help prevent a blood clot from forming. Moving your legs, even if you can’t walk or put weight on them, may help keep blood circulating.

Another preventive measure may also be necessary. A device known as a vena cava filter can be surgically implanted in a large vein in your midsection called the vena cava. It’s made with a mesh material that allows blood to circulate back to the heart, but it screens out blood clots that have formed in the legs. It doesn’t prevent blood clot formation, but it can help keep those clots from reaching the lungs.

If you have had VTE in the past, a vena cava filter may be a good idea. Talk with your doctor about this and other preventive measures.

If you were on anticoagulants for a previous VTE, daily aspirin therapy may be a safe and effective way to help prevent recurrent VTE.

VTE is serious but is often preventable. Preventing recurrent VTE may require medications and other procedures, but the benefits of avoiding this circulation problem are worth it.