Venous Thromboembolism: Deep Vein Clots and Pulmonary Embolism

Key points

• Venous thromboembolism (VTE) means blood clots in the veins: deep vein thrombosis (DVT) and pulmonary embolism (PE).
• DVT: a clot in a deep vein, most often in the leg. It needs prompt medical care.
• PE: part of the clot breaks off and travels to the lungs. It needs immediate care.
• Both are serious but often preventable.

VTE can happen to anyone and can cause serious illness, disability and sometimes death. It is often underdiagnosed — but often preventable and treatable. Know the signs, know your risk, and seek care.

Signs and symptoms

DVT — about half of people have no symptoms. In the affected leg or arm, look for:

• swelling;
• pain or tenderness;
• warmth;
• redness or discoloration.

See a doctor as soon as possible.

PE — can happen without DVT symptoms:

• difficulty breathing;
• a fast or irregular heartbeat;
• chest pain or discomfort, usually worse with a deep breath or cough;
• coughing, or coughing up blood;
• very low blood pressure, lightheadedness or fainting.

Get medical help immediately.

Risk factors

Almost anyone can get a DVT or PE. Risk rises with:

• injury to a vein;
• slow blood flow from limited movement;
• some chronic illnesses, older age, family history and other factors;
• higher estrogen levels.

More: risk factors for blood clots.

Complications

• PE: with a small clot and treatment, people can recover, though the lungs may be damaged. After a large clot, chronic thromboembolic pulmonary hypertension can block blood from the lungs and be fatal.
• Post-thrombotic syndrome: one-third to one-half of people with DVT develop it, from clot damage to vein valves — swelling, pain, discoloration, and in severe cases scaling or ulcers, sometimes disabling.
• Recurrence: about 30% of people who've had a DVT or PE are at risk of another.

Prevention

• Move as soon as you can after bed rest from surgery, illness or injury.
• At risk? Ask your doctor about graduated compression stockings and anticoagulant medicine.
• Long sitting — such as travel over 4 hours: walk around every 1 to 2 hours, wear loose clothes, and exercise your legs in your seat: raise and lower your heels (toes down), then your toes (heels down), and tighten and release your leg muscles.
• Keep a healthy weight, stay active, and follow your doctor's advice.

Diagnosis and treatment

Diagnosis needs special tests by a doctor — another reason to seek care for any sign. See testing and diagnosis.

• DVT: medicine; compression stockings may ease pain and swelling and help prevent DVT, sometimes for 2 years or more; in severe cases, surgical clot removal.
• PE: immediate care. For severe, life-threatening PE, thrombolytics dissolve the clot; anticoagulants prevent new ones, sometimes long-term.

Did you know?

DVT does not cause heart attack or stroke. There are two main kinds of clot:

The causes and prevention differ; see CDC's heart disease and stroke prevention.

Guidelines

In November 2018, the American Society of Hematology (ASH), working with the McMaster University GRADE Centre, hematologists, other clinicians, guideline specialists and patient representatives, released the 2018 ASH Clinical Practice Guidelines on Venous Thromboembolism.

Sources

Based on "About Venous Thromboembolism (Blood Clots)," Centers for Disease Control and Prevention; a work of the United States government in the public domain. The page's stock images are left out.