Deep Vein Thrombosis

What is deep vein thrombosis?

Deep vein thrombosis (DVT) is a blood clot in a deep vein. A blood clot, also called a thrombus, is a gel-like clump made of blood and platelets (cells that work to stop bleeding). Deep veins are large blood vessels that run through muscles and along bones.

Your body has a network of blood vessels that carry blood to and from your heart. Deep veins bring deoxygenated blood from around your body back to your heart. They connect to the smaller veins (superficial veins) that you can see beneath your skin.

A blood clot can also form in these superficial veins, called superficial vein thrombosis (SVT). DVT and SVT may have similar symptoms, but DVT can lead to more serious complications than SVT if the blood clot moves. While SVT may cause redness or soreness in one area of the leg, it typically carries a lower risk of serious complications than DVT.

DVT most frequently develops in the legs. It can also form in the arms, abdomen, or brain. Usually, DVT only affects a vein in one side of your body. Vascular specialists at the Mass General Brigham Heart and Vascular provide expert DVT care.
 

Deep vein thrombosis and pulmonary embolism

DVT can cause a life-threatening condition called pulmonary embolism. A pulmonary embolism is a blood clot that blocks blood flow in the lungs. It develops when part of a deep vein blood clot (embolus) dislodges and travels through the bloodstream to the lungs.

Both DVT and pulmonary embolism are types of venous thromboembolism (a blood clot in a vein). You may hear healthcare providers use this medical term to refer to either of these conditions.

Symptoms of deep vein thrombosis

Most DVT symptoms occur where the blood clot develops, such as in your leg or arm. Symptoms range from mild to severe. Some people may not experience any signs of DVT until it causes a pulmonary embolism.

Common symptoms include:

• Mild fever
• Pain that feels deep inside your muscle
• Redness or skin discoloration
• Swelling
• Tenderness or cramping
• Warm skin

When is deep vein thrombosis an emergency?

You should see a healthcare provider as soon as possible if you experience any symptoms of DVT and blood clots in your legs, such as unusual pain or swelling. Seek emergency care if you have symptoms of a pulmonary embolism, including:

• Chest pain
• Coughing up blood
• Difficulty breathing
• Dizziness or fainting
• Excessive sweating
• Racing heart

Causes of deep vein thrombosis

DVT can develop from blood moving too slowly, damage inside a vein, or increased blood clotting. These problems interfere with blood flow and can cause a blood clot to form. In rare cases, DVT is caused by pressure on a vein from outside the body, such as in a condition called thoracic outlet syndrome.

Risk factors for deep vein thrombosis

Risk factors increase your chance of developing DVT. Talk with your Mass General Brigham provider about your health history, family history, and lifestyle. We can help you manage your risk and prevent DVT.

Things that affect blood flow and vein health can increase your risk, including:

• Aging over 60 years old
• A long-term catheter (thin tube) in a blood vessel, called a central line or central venous catheter
• Fractured or broken bones that keep you from moving regularly
• Having a family history of blood clots
• Muscle injury
• Obesity
• Pregnancy or recently giving birth
• Recent surgery, especially catheter-based surgery (which accesses inside your body through a vein in your groin or arm)
• Sitting or lying down for a long time, such as long flights, drives, or bed rest

You also face a higher risk for DVT if your blood clots more easily. Blood clotting can increase for several reasons, including:

• Autoimmune diseases
• Blood clotting disorders
• Cancer
• Hormonal birth control
• Hormone replacement therapy
• Smoking

Preventing deep vein thrombosis

You can take certain steps to prevent blood clots and reduce your risk for DVT. Talk to your provider about recommended lifestyle changes or medications based on your risk factors. Try to:

• Avoid smoking and drinking alcohol
• Get up and walk often if possible on long trips or after surgery
• Keep a healthy weight and exercise regularly
• Move your legs, ankles, and toes often if sitting or lying down for a long time
• Stay hydrated
• Take blood thinners and other anti-clotting medication as prescribed by your provider
• Use compression devices as prescribed by your provider during long hospital stays
• Wear compression stockings as prescribed by your provider
• Wear loose clothing

Diagnosing deep vein thrombosis

Our vascular specialists do a complete evaluation to diagnose DVT as soon as possible and prevent serious complications. We review your medical history for possible causes of DVT, such as medications or existing health conditions. We also do a physical exam of the affected area.

You may undergo a range of diagnostic tests for DVT, including:

• Blood tests, to check for blood clotting disorders
• CT scan or MRI scan, to look at blood vessels in your abdomen or pelvic area
• Duplex ultrasound, which uses two types of ultrasound imaging (Doppler and B-mode) to assess blood flow and blood vessels
• Venography, which uses a special dye injected into your bloodstream to see blood flow and vein health on X-ray images

Treatment for deep vein thrombosis

Our vascular team at Mass General Brigham specializes in all types of vein diseases, including DVT. Your provider may work together with cardiologists and your primary care provider to support your overall cardiovascular health.

We treat most DVT with medication that prevents new blood clots from forming and keeps existing ones from growing. You may receive medication in pill form, as an injection, or intravenously (directly into your bloodstream).

Most people need to take anti-clotting medication for three months or longer. Your medication dosage depends on the severity of the blood clot and your risk of getting another clot in the future. We personalize your medical treatment plan to your needs.

DVT medications include:

• Blood thinners (anticoagulants), which thin your blood to prevent clotting
• Clot busters (thrombolytics), which work to break up and dissolve large, severe blood clots

Some DVT may require more complex treatment. We offer advanced and minimally invasive procedures to target blood clots. We may need to do a procedure to:

• Deliver clot-busting medication more directly into the vein
• Put a device called an inferior vena cava filter inside a major vein to block blood clots from getting to your heart and lungs
• Remove the blood clot

If the DVT is caused by compression of the vein, such as in thoracic outlet syndrome, surgical treatment may be necessary to relieve the pressure, which often involves removing a rib and surrounding muscle attachments to decompress the vein.