by Dana P. Launer, MD
Deep vein thrombosis, commonly referred to as DVT, is a condition where a blood clot forms in one of the larger or “deep” veins in your body, most often in your thigh and lower leg.
The clot may cause circulation problems by partially or completely blocking the flow of blood through the vein, or a smaller piece may break off and travel through the blood stream, where it can get trapped in the heart, lungs — or, rarely, the brain — and cause serious problems.
Complications from DVT result in 200,000 deaths every year in the U.S. A clot that disrupts the flow of blood to the brain can cause a stroke, while one that travels to the lungs can block the pulmonary artery.
The result can be pulmonary embolism, a life-threatening condition marked by shortness of breath, chest pain, and a bloody cough.
While DVT most commonly affects people age 60 and older, other factors can increase your risk as well. DVT is more likely to develop in people who are immobilized for long periods of time, such as after surgery or an injury.
Long periods of sitting still, such as in an airplane, can cause blood to “pool” in the legs, disrupting its normal flow through the veins. Illnesses, including certain types of cancer, clotting disorders and inflammatory diseases may also contribute to the development of DVT.
Hormones may play a role, too. Pregnant women are five times more likely than non-pregnant women to develop DVT, especially in their third trimester and immediately after delivery. Women who use oral contraceptives or hormone replacement therapy also have a greater risk of DVT.
Because the symptoms can be very mild, DVT often goes unnoticed. Blood clots typically occur only in one leg and can cause pain, tenderness, swelling, unusual warmth, redness, or changes in skin color.
If you notice any of these symptoms, call your doctor. He or she will examine your legs and may order an ultrasound test, which uses sound waves to evaluate blood flow through the veins and indicates whether there is a blockage or obstruction.
Because veins normally do not show up in an X-ray, occasionally a contrast material is injected into the vein to make it visible, and the images are taken as the material flows through the vein.
Given the serious complications of DVT, it’s important to get treatment promptly to help prevent pulmonary embolism and other problems.
Your doctor may treat you with an intravenous anticoagulant, such as heparin, to clear the blood clot. In addition, your doctor may prescribe warfarin, an oral medication that increases the time it takes for blood to clot and helps ward off DVT.
Most patients take warfarin for several months or more following treatment with heparin. In some cases, surgery may be recommended to remove the clot.
Early treatment for DVT is usually very effective. However, people who have one episode of DVT have a higher risk of recurrence. Some may have chronic pain and swelling in their leg as well, and may need to take special precautions to minimize the risk of complications.
Because the risk of DVT is highest among people who are immobile for long periods, it’s a good idea to avoid sitting or standing still for hours at a time.
If you work at a desk, take frequent breaks to get up, walk around, and get your circulation going. During airplane travel, make a point of walking up and down the aisles every hour or so.
Talk to your doctor if you are planning a long flight; he or she may prescribe a single dose of an anticoagulant to head off problems.
Your doctor also may recommend that you wear special stockings known as “compression stockings” to help minimize the risk of developing DVT. These stockings put pressure on leg muscles and help blood flow from the legs back to the heart.
This Scripps Health and Wellness information was provided by Dana P. Launer, MD, chief of staff at Scripps Memorial Hospital La Jolla.