Complications of Deep Vein Thrombosis

Deep vein thrombosis (DVT) is a condition involving the formation of a blood clot or thrombus in a deep vein. One may develop in a large vein deep inside the leg, arm, or other part of the body. Complications from deep vein thrombosis 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 the two conditions are very closely related. And, because their prevention and treatment are closely related. 


Outline of human torso showing heart, lungs, and major veins. Blood clot is in leg vein with arrow showing it traveling up vein to lung causing pulmonary embolism.


Pulmonary embolism

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


When to seek medical advice

Call 911 or emergency help 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 you have symptoms of a blood clot. The symptoms include:

  • Swelling

  • Pain

  • Redness in your leg, arm, or other area

Call your healthcare provider if you have signs or symptoms of bleeding, like blood in the urine, bleeding with bowel movements, or bleeding from the nose, gums, a cut, or vagina.

Chronic venous insufficiency and post-thrombotic syndrome

Two other complications of deep vein thrombosis are chronic venous insufficiency and post-thrombotic syndrome.

Chronic venous insufficiency may happen following deep vein thrombosis of a leg vein. It means that a vein no longer works as well. It is 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 may also happen following deep vein thrombosis of a leg vein. It is a long-term problem with pain, swelling, and redness. Ulcers and sores can also happen if the condition is not treated early. These complications and associated symptoms may make it difficult to walk and take part in daily activities.