By Brian P. Dunleavy Medically Reviewed by Robert Jasmer, MD foe everydayhealth.com
DVT can be fatal if left undiagnosed or untreated.
Deep vein thrombosis (DVT) is caused by a blood clot that forms in one or more of the deep veins in your body, typically in your legs.
DVT can be serious: Blood clots in your veins can break loose and move to your lungs, causing a pulmonary embolism, which can be fatal.
The Centers for Disease Control and Prevention (CDC) estimates that 900,000 Americans are diagnosed with DVT annually.
As many as 100,000 Americans die from DVT each year.
DVT Symptoms and Diagnosis
If you have DVT, you may experience leg pain or swelling. However, the condition can occur without any symptoms.
If you see signs or symptoms of DVT, talk to your doctor. If you have symptoms of a pulmonary embolism, seek emergency medical assistance immediately.
Signs of a pulmonary embolism include:
Unexplained or sudden shortness of breath
Chest pain or discomfort that worsens when you take a deep breath or cough
Dizziness or fainting
Coughing up blood
About 25 percent of people with a pulmonary embolism experience sudden death before the condition is diagnosed, according to the CDC.
To check for DVT, your doctor may recommend:
An ultrasound of your deep veins to check for clots
A blood test to check for elevated levels of D-dimer (a sign of DVT)
A venography X-ray of the veins in your legs and feet to check for clots
A CT scan or MRI scan of your deep veins to check for clots
DVT Causes and Risk Factors
Deep vein thrombosis can result from certain medical conditions that affect how your blood clots, including:
Inherited blood clot disorders
Medical treatment requiring long hospital stays or bed rest
Injuries to the legs that affect the veins
Being overweight or obese
Use of birth control pills or hormone replacement therapy
Congestive heart failure
Inflammatory bowel disease (Crohn’s disease or ulcerative colitis)
Some types of cancer, or cancer treatment, may increase levels of certain substances in your blood that cause clots.
If you have heart failure, you are at increased risk for DVT and pulmonary embolism due to limited heart and lung function.
Being overweight or obese increases the pressure in the veins of your legs and pelvis, raising the risk of clots.
This risk also increases during pregnancy (women with an inherited clotting disorder are at higher risk) and for up to 6 weeks after giving birth.
Using birth control pills (oral contraceptives) or hormone replacement therapy (HRT) can increase your blood’s clotting abilities.
Smoking adversely affects blood clotting and circulation, which can increase your risk of DVT.
If you or someone in your family has had DVT or a pulmonary embolism before, you are more likely to develop DVT.
Being over 60 increases your risk of DVT, even though it can occur at any age.
Finally, sitting for long periods of time (as happens in airplane travel or long car trips) can increase your risk for DVT.
Blood clots may form in your calves if the muscles aren’t moved for extended periods.
Treatment options for DVT include:
Anticoagulants (blood thinners)
Surgery to remove the clot
Anticoagulants, or blood thinners, are usually the first-choice treatment for DVT.
Although anticoagulants don’t break up existing clots, they can prevent the clot from growing in size, and prevent new clots from forming.
When you start anticoagulation therapy that’s given by injection, your doctor will often administer the first few doses of the blood thinner, after which you may be able to administer the injections on your own.
Examples of injectable blood thinners include:
If your doctor prescribes oral anticoagulation therapy, such as Coumadin (warfarin), Xarelto (rivaroxaban), Eliquis (apixaban), or Savaysa (edoxaban), you will typically take these medications for three months or longer.
Your doctor will also recommend regular blood tests to check how long it takes for your blood to clot.
All blood thinners must be taken as prescribed to avoid serious side effects.
Thrombolytics (also known as tissue plasminogen activators) are given intravenously (by IV) or through a catheter directly to an existing blood clot. They are designed to break up clots.
Thrombolytics can cause serious bleeding. They are used only in life-threatening situations, and only if you are hospitalized.
If you are unable to take blood thinners for any reason, your doctor may recommend a minor surgical procedure in which a filter is inserted into a large vein in your abdomen, known to doctors as the inferior vena cava.
This filter is designed to prevent any clots that break loose from traveling to your lungs.
Finally, wearing compression stockings on your legs can help prevent swelling associated with DVT. The pressure they create lowers the risk of blood pooling and clotting.
Pulmonary embolism is the most troubling complication associated with DVT.
A pulmonary embolism occurs when a blood vessel in your lung is blocked by a blood clot that has moved from another part of your body, usually the deep veins in your legs. It can be fatal if left untreated.
Post-thrombotic syndrome (also called post-phlebitic syndrome) is another common complication associated with DVT.
It’s caused by damage to your veins from a blood clot that reduces blood flow in the affected areas.
Signs and symptoms of post-thrombotic syndrome include:
Swelling or pain in your legs
Finally, pulmonary hypertension (elevated blood pressure in your pulmonary artery) is a rare complication of pulmonary embolism.
It occurs when the clots do not dissolve and the arteries of the lungs continue to be obstructed.
Deep Vein Thrombosis / Pulmonary Embolism; CDC.
Deep Vein Thrombosis; Mayo Clinic.
Deep Vein Thrombosis; MedlinePlus/NIH.