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Sidestepping deep vein thrombosis
Various clot causes
Telltale signs
PE: Medical emergency

Keeping clots at bay
Keeping clots at bay

Unfortunately, DVT returns in one out of every three patients within five years. Doctors are unsure how to prevent DVT from developing, but it seems that exercising, avoiding long periods of sitting and elevating the legs can be helpful.

A 2003 nationwide study for recurrent DVT or PE patients—called Prevention of Recurrent Venous Thromboembolism (PREVENT)—found long-term, low-dose treatment with warfarin prevents the recurrence of DVT with no adverse effects. The study—conducted by the National Heart, Lung, and Blood Institute—involved more than 500 participants. Ask your healthcare provider if long-term, low-dose warfarin treatment may be right for you.

Pain from clots in the leg veins can not only be agonizing, it also signals a health threat that may damage the leg and lead to even more serious heart and lung complications. Fortunately, this condition—called deep vein thrombosis (DVT)—is treatable, but early diagnosis is paramount.

That’s because the clot can break away from its location in the leg and travel to the lungs. Once there, it may block a lung artery and cause a potentially fatal pulmonary embolism. Patients diagnosed with DVT must be hospitalized to receive prompt emergency care and avoid complications.

Various clot causes

Though DVT runs in some families, doctors say that many times these clots form for no apparent reason. Men and women of all ages and races can be affected. However, doctors have identified some of the risk factors for DVT, including:

  • obesity
  • inactivity
  • an above-normal tendency for blood to clot
  • recent surgery
  • heart attack
  • a recent hip or leg fracture
  • prolonged car or plane travel (“economy-class syndrome”)
  • pancreatic and certain other cancer treatments in which procoagulants—blood-clotting agents—form in the bloodstream

Telltale signs

The onset of DVT is usually marked by inflammation and swelling of the leg as well as redness, pain, tenderness and a sensation of heat radiating from the location of the clot. There also seems to be a correlation with the seasons: A French study finds DVT hospitalizations rise 18 percent above average in winter and drop 18 percent below average in summer, probably due to cold air narrowing blood vessels and people’s reduced activity levels during winter.

Once DVT is diagnosed, usually with a Doppler ultrasound scan, a blood-thinning agent called heparin is given intravenously to keep the clot from getting bigger. The body will dissolve the clot in time. Then, an oral anticoagulant called warfarin is given to keep the clot from re-forming.

Warfarin therapy usually lasts from three to six months, but the dosage levels occasionally need adjusting. Too much warfarin causes patients to bruise easily and bleed profusely from even minor cuts. Because of these risks, warfarin therapy seldom continues past 180 days.

PE: Medical emergency

Vigorously attacking the clot is meant to sidestep a more troublesome problem called a pulmonary embolism, or PE. This complication arises when part of the clot detaches and winds up lodged in a lung artery.

Symptoms of PE include chest pain, shortness of breath, a cough that produces blood or, in severe cases, unconsciousness. One out of every 10 patients who develops PE dies within the first hour. If diagnosed in time, however, a PE patient usually recovers within several weeks.