Deep Vein Thrombosis

Learn more about deep vein thrombosis (DVT), including risks, symptoms, diagnosis, treatment, prevention, and safety.

What is Deep Vein Thrombosis?

Deep vein thrombosis (DVT) is the formation of a blood clot in the deep leg vein. It is a very serious condition that can cause permanent damage to the leg or a life-threatening pulmonary embolism. In the United States alone, 600,000 new cases are diagnosed each year. One in every 100 people who develops DVT dies. Recently, it has been referred to as “Economy Class Syndrome” due to the occurrence after sitting on long flights.

The deep veins that lie near the center of the leg are surrounded by powerful muscles that contract and force deoxygenated blood back to the lungs and heart. One-way valves prevent the back-flow of blood between the contractions. (Blood is squeezed up the leg against gravity and the valves prevent it from flowing back to our feet.) When the circulation of the blood slows down due to illness, injury or inactivity, blood can accumulate or “pool,” which provides an ideal setting for clot formation.

Deep Vein Thrombosis Risk Factors

  • Previous DVT or family history of DVT
  • Immobility, such as bed rest or sitting for long periods of time
  • Recent surgery
  • Above the age of 40
  • Hormone therapy or oral contraceptives
  • Pregnancy or post-partum
  • Previous or current cancer
  • Limb trauma and/or orthopedic procedures
  • Coagulation abnormalities
  • Obesity
  • Smoking

Deep Vein Thrombois Symptoms

  • Discoloration of the legs
  • Calf or leg pain or tenderness
  • Swelling of the leg or lower limb
  • Warm skin
  • Surface veins become more visible
  • Leg fatigue
  • Some people with DVT may have no symptoms

Pulmonary Embolism

Left untreated, a deep vein thrombosis (DVT) can break off and travel in the circulation, getting trapped in the lung, where it blocks the oxygen supply, causing heart failure. This is known as a pulmonary embolism, which can be fatal. With early treatment, people with DVT can reduce their chances of developing a life-threatening pulmonary embolism to less than one percent. Blood thinners like heparin and coumadin are effective in preventing further clotting and can prevent a pulmonary embolism from occurring.
  • It is estimated that each year more than 600,000 patients suffer a pulmonary embolism
  • PE causes or contributes to up to 200,000 deaths annually in the United States
  • One in every 100 patients who develop DVT die due to pulmonary embolism
  • A majority of pulmonary embolisms are caused by DVT
  • If pulmonary embolism can be diagnosed and appropriate therapy started, the mortality can be reduced from approximately 30 percent to less than ten percent


  • Symptoms are frequently nonspecific and can mimic many other cardiopulmonary events
  • Shortness of breath
  • Rapid pulse
  • Sweating
  • Sharp chest pain
  • Coughing up blood
  • Fainting

Preventing Deep Vein Thrombosis

You can reduce your risk by:

  • Exercising regularly
  • Maintaining a healthy weight
  • Not smoking
  • Moving around as soon as you’re able following long-term bed rest

When sitting for long periods of time, such as when traveling for more than six hours:

  • Exercise your legs frequently while you’re sitting
  • Get up and walk around every 2 to 3 hours
  • Wear loose-fitting clothes
  • Drink plenty of water, and limit alcohol and caffeine while traveling

Information posted on this Web site by SIR or Coastal Vascular & Interventional, PLLC should not be considered medical advice and is not intended to replace consultation or discussion with an interventional radiologist or vascular surgeon. It is very important that individuals with specific medical problems or questions consult with their doctor or other health care professional.

“Reprinted with permission of the Society of Interventional Radiology 2004, 2011, All rights reserved.”