Complications of Deep Vein Thrombosis

Deep vein thrombosis (DVT) is a condition where a blood clot (thrombus) forms in a deep vein. It may develop in a large vein deep inside the leg, arm, or other part of the body. Complications from DVT can be very serious. They can include pulmonary embolism (PE), chronic venous insufficiency, and post-thrombotic syndrome. 

You may hear healthcare providers use the term venous thromboembolism (VTE) to describe DVT and PE. They use the term VTE because these conditions are very closely linked. And because their prevention and treatment are closely linked.

Pulmonary embolism

Pulmonary embolism (PE) happens when part of the clot, called an embolus, separates from the vein. It goes to the lungs and cuts off blood flow. A PE may develop quickly. It's a medical emergency and may cause death. 

Front view of male figure with arrow showing path of blood clot from leg vein to lung, causing pulmonary embolism. 

Call 911

Call 911 if you have symptoms of a blood clot in the lungs. Symptoms may include:

  • Chest pain

  • Trouble breathing or sudden shortness of breath

  • Coughing (may cough up blood)

  • Fainting

  • Fast heartbeat

  • Sweating

You may have bleeding if you take medicine to help prevent blood clots. Call 911 if you have heavy or uncontrolled bleeding.

When to call your healthcare provider

Call your healthcare provider if any of these occur:

  • You have symptoms of a blood clot, such as:

    • Swelling
    • Pain
    • Redness in your leg, arm, or other area

  • You have symptoms of bleeding, such as:

    • Blood in your urine
    • Bleeding with bowel movements
    • Bleeding from your nose or gums
    • Bleeding from a cut
    • Bleeding from the vagina

Chronic venous insufficiency and post-thrombotic syndrome

Two other complications of DVT are chronic venous insufficiency and post-thrombotic syndrome.

Chronic venous insufficiency.  This may happen following DVT of a leg vein. It means that a vein no longer works as well. It's a long-term condition where blood stays in the vein instead of flowing back to the heart. Pain and swelling in the leg are common symptoms.

Post-thrombotic syndrome. This may also happen after DVT of a leg vein. It's a long-term problem with pain, swelling, and redness. Ulcers and sores can also happen if the condition isn't treated early. These complications and related symptoms may make it hard to walk and take part in daily activities.