Deep Vein Thrombosis

Overview

What is deep vein thrombosis?

Deep vein thrombosis (also called DVT) is a blood clot in a vein deep inside your body. These clots usually occur in your leg veins. While DVT is a fairly common condition, it is also a dangerous one. If the blood clot breaks away and travels through your bloodstream, it could block a blood vessel in your lungs. This blockage (called a pulmonary embolism) can be fatal.

Symptoms

What are the symptoms of DVT?

Some people have no symptoms at all. Most have some swelling in one or both legs. Often there is pain or tenderness in one leg (may happen only when you stand or walk). You may also notice the skin feel warm or looks red or discolored in the affected leg. If you have any of these symptoms, call your doctor right away.

Causes & Risk Factors

Am I at risk for DVT?

You are at higher risk for DVT if you:

Your risk for DVT increases if you have several risk factors at the same time.

  • Are 60 years of age or older

  • Are inactive for a long period of time, such as when you are flying in an airplane, taking a long car trip or recovering in bed after surgery

  • Have inherited a condition that causes increased blood clotting

  • Have an injury or surgery that reduces blood flow to a body part

  • Are pregnant or have recently given birth

  • Are overweight or obese

  • Have varicose veins

  • Have cancer, even if you are being treated for it

  • Are taking birth control pills or receiving hormone therapy, including for postmenopausal symptoms

  • Have a central venous catheter

Diagnosis & Tests

How does my doctor diagnose DVT?

If your doctor thinks you might have DVT, he or she will perform some tests to find out. These may include an ultrasound (a test that uses sound waves to check the blood flow in your veins) or venography (a doctor injects dye into your vein, then takes an X-ray to look for blood clots).

Treatment

What medicines are used to treat DVT?

The following are the main goals in treating DVT:

Several medicines are used to treat or prevent DVT. The most common are anticoagulants (also called blood thinners) such as warfarin or heparin. Anticoagulants thin your blood so that clots won’t form. Warfarin is taken as a pill and heparin is given intravenously (in your veins). If you can’t take heparin, your doctor may prescribe another kind of anticoagulant called a thrombin inhibitor.

  • Stopping the clot from getting bigger.

  • Preventing the clot from breaking off and traveling to your lungs.

  • Preventing any future blood clots.

What are the side effects of anticoagulants?

Anticoagulants can cause you to bleed more easily. For example, you might notice that your blood takes longer to clot when you cut yourself. You might also bruise more easily. If you have any unusual or heavy bleeding, call your doctor right away.

Warfarin can cause birth defects. Women who are pregnant shouldn’t take warfarin.

Some other medicines can affect how well an anticoagulant works. If you’re taking an anticoagulant, ask your doctor before you take any new medicine, including over-the-counter medicines or vitamins. Certain foods rich in vitamin K, such as dark green vegetables, can also affect how well an anticoagulant works.

What other treatments are used for DVT?

If you can’t take medicine to thin your blood, or if a blood thinner doesn’t work, your doctor may recommend that you have a filter put into your vena cava (the main vein going back to your heart from your lower body). This filter can catch a clot as it moves through your bloodstream and prevent it from reaching your lungs. This treatment is used mostly for people who have had several blood clots travel to their lungs.

Elevation of the affected leg and compression can help reduce swelling and pain from DVT. Your doctor can prescribe graduated compression stockings to reduce swelling in your leg after a blood clot has developed. These stockings are worn from the arch of your foot to just above or below your knee. They cause a gentle compression (pressure) of your leg.

Prevention

How can I prevent DVT?

  • Frequently exercise your lower leg muscles if you’ll be inactive for a long period of time. Stretch your legs and lightly massage your muscles. If you can, get up every hour or so and walk around. If you must stay seated, try lifting your heels (with your toes still on the ground) and then lifting your toes (with your heels still on the ground) to stretch your calves.

  • Get out of bed and move around as soon as you can after having surgery or being ill.

  • After some types of surgery, take medicine to prevent blood clots as directed by your doctor.

  • Control your blood pressure, don’t smoke and lose weight if you’re overweight. High blood pressure, being a smoker and being overweight make you more likely to develop DVT.

Questions to Ask Your Doctor

  • What is the likely cause of my deep vein thrombosis?

  • What is the treatment for this blood clot? Medicine? Surgery?

  • Am I at risk for pulmonary embolism?

  • Am I at risk for having another blood clot in the future?

  • Do I need to take an anticoagulant to prevent blood clots? For how long?

  • Do I need to make any lifestyle changes to reduce my risk of blood clots?

  • Is it safe for me to travel?

  • Does deep vein thrombosis increase my risk for other health problems?