What are the symptoms of DVT?

A DVT usually forms in one leg or one arm. Not everyone with a DVT will have symptoms, but symptoms can include:

  • Swelling of the leg or arm (sometimes this happens suddenly)
  • Pain or tenderness in the leg (may only happen when standing or walking)
  • The area of the leg or arm that is swollen or hurts may be warmer than usual
  • Skin that is red or discolored
  • The veins near the skin’s surface may be larger than normal

Symptoms of a pulmonary embolism include:

  • Sudden shortness of breath or fast breathing
  • Sharp chest pain that often comes with coughing or movement
  • Pain in the back
  • Cough (sometimes with bloody sputum/phlegm)
  • Sweating more than normal
  • Fast heartbeat
  • Feeling dizzy or fainting

Some people do not know they have a DVT until the clot moves from their leg or arm and travels to their lung.

It is important to call your doctor right away or go to the emergency room if you have symptoms of a pulmonary embolism or DVT. Do not wait to see if the symptoms “go away.” Get treatment right away to prevent serious complications.

What causes a DVT?

The following conditions can increase your risk of a DVT:

  • An inherited (genetic) condition that increases your risk of blood clots
  • Cancer and some of its treatments (chemotherapy)
  • Limited blood flow in a deep vein, due to injury, surgery, or immobilization
  • Long periods of inactivity that decrease blood flow, such as:
    • Sitting for a long period of time on trips in a car, truck, bus, train or airplane
    • Immobility after surgery or a serious injury
  • Pregnancy and the first 6 weeks after giving birth
  • Being over age 40 (although a DVT can affect people of any age)
  • Being overweight
  • Taking birth control pills or hormone therapy
  • Having a central venous catheter or pacemaker

How is DVT diagnosed?

An appointment to find out if you have a DVT includes an exam and review of your medical history. You will also need testing. Common tests to diagnose a DVT are:

A duplex venous ultrasound. This is the most common test used to diagnose a DVT. It shows the blood flow in the veins and any blood clots that exist. An ultrasound technician will apply pressure while scanning your arm or leg. If the pressure does not cause the vein to compress, it could mean there is a blood clot.

Venography. This test uses X-rays to show your deep veins. A special dye (contrast material) is injected into your veins so the X-rays show the veins and any blood clots. Any blockage in blood flow may also be seen. Venography may be used if the results of the duplex ultrasound aren’t clear.

Other tests you may have include:

  • Magnetic Resonance Imaging (MRI) or Magnetic Resonance Venography (MRV): MRI shows pictures of organs and structures inside the body, and MRV shows pictures of the blood vessels in the body. In many cases, MRI and MRV can offer more information than an X-ray.
  • Computed tomography (CT) scan is a type of X-ray that shows structures inside the body. A CT scan may be used to find a DVT in the abdomen or pelvis, as well as blood clots in the lung (pulmonary embolism).

If your doctor thinks you may have a genetic disorder that causes blood clots, you may need blood tests. This may be important if:

  • You have a history of blood clots that cannot be linked to any other cause
  • You have a blood clot in an unusual location, such as in a vein from the intestines, liver, kidney or brain
  • You have a strong family history of blood clots

Reviewed: 05/17