What is Deep Vein Thrombosis?

Deep Vein Thrombosis (DVT) is a blood clot that forms in the deep veins of the body, typically in the lower leg or thigh. The clot can move through your body and block your blood vessels, leading to serious medical conditions, including pulmonary embolism (PE), heart attack, or stroke. 

What Causes DVT? 

Deep vein thrombosis is caused by a blood clot. It occurs when a clot forms in the deep veins, which are found deep within the body. Inactivity is one of the most common causes of DVT.  

Your blood doesn’t flow very well when you don’t move around. Your muscles are not contracting when you are sitting still or lying down, so your blood flow is sluggish. Any injury to the vein wall (even a small one) can cause scarring, leading to clots forming more easily. A clot makes it even harder for the blood to flow properly, leading to further problems with circulation.  

Other causes of DVT include injuries and surgery, especially surgeries that require long periods of inactivity like hip replacement or knee replacement surgery. Aging increases the likelihood of getting DVT because as people age, they usually become less active and have more medical conditions that can increase their risk of developing clots. 

People who have had previous episodes of DVT or pulmonary embolism (PE) or have a family history of these conditions are at higher risk of getting them again. 

Those who smoke and are overweight also increase their chances of developing clots. 

What are the Symptoms of DVT? 

Symptoms of DVT include,  

  • Swelling: One of the most common symptoms, swelling may only occur in one leg. 
  • Warm Skin: Skin that’s warm to the touch may indicate circulation problems in your legs. 
  • Discoloration: Your legs may appear reddish or bluish. 
  • Pain or tenderness: You might experience pain or tenderness in your calves and/or thighs. 
  • Cramps, itchiness, and throbbing veins are also common symptoms of DVT. 

But it’s important to note that many people with Deep Vein Thrombosis don’t experience any symptoms. 

How is DVT Diagnosed? 

A Vascular Surgeon diagnoses DVT by examining the legs, a blood test, and an ultrasound. If the physician suspects DVT in a patient, they will first examine the legs for signs of pain, swelling, or warmth. They may also ask about symptoms such as redness of the skin or veins that are tender to the touch.  

If the physical examination is suspicious of DVT, the doctor will order blood tests. These blood tests measure a substance found in high levels when blood clots are present. The selection of appropriate tests depends on the patient’s age, risk factors, clinical presentation, and suspected type of thrombus (blood clot). The following tests may be used: 

D-Dimer Test: This blood test can detect fragments of DNA released by dead blood clots

Prothrombin Time (PT) and Activated Partial Thromboplastin Time (APTT) are blood clotting tests. 

Elevated D-dimer levels, as well as abnormal results from the PT and APTT tests, help to confirm the presence of DVT. 

Ultrasound Imaging can also help to rule out DVT in many cases. For example, if a person has lower leg pain, swelling, or redness but their D-dimer level is normal, they likely do not have a blood clot in their leg. However, if the D-dimer level suggests a blood clot might present, an ultrasound scan could be used to confirm this suspicion. 

Magnetic Resonance Imaging (MRI) or Magnetic Resonance Venography (MRV): Magnetic Resonance Imaging (MRI) or Magnetic Resonance Venography (MRV) — MRI produces a detailed image of blood vessels and soft tissues. An MRI scan may be ordered when other tests are inconclusive. MRV is an MRI test that uses a contrast agent to produce more detailed images of blood vessels in the leg. 

Computed Tomography (CT) scan is a series of X-rays that provide detailed pictures of your blood vessels and organs. Your doctor may use a CT scan to help diagnose or rule out DVT. Your doctor may also want to check for complications of DVT, such as pulmonary embolism. 

How is DVT Treated? 

The primary goal of treating a DVT is to stop the clot from getting bigger and prevent the clot from breaking off and traveling to the lungs, where it can cause a life-threatening condition known as a pulmonary embolism (PE). Treatment for a DVT includes medications, lifestyle changes, and/or interventional procedures. 


Your doctor may prescribe anticoagulants (blood thinners) which help keep clots from getting bigger. They also prevent new clots from forming. Thrombolytics are “clot busters.” These medicines help dissolve blood clots. 

Lifestyle Changes: 

Elevate Your Leg. Using pillows, raise your leg above the level of your heart while lying down, if you can. This slows blood flow back to your leg veins, decreasing swelling and pain. 

Wear Compression Stockings or Socks. These garments squeeze on your legs to reduce swelling and pain and improve circulation. Ask your doctor when you should wear them and for how long. Compression stockings come in different sizes, lengths, and strengths (also called compression levels). Your doctor will tell you which type you should get. 

Interventional Procedures:  

Some of the interventional procedures for patients with a Deep Vein Thrombosis (DVT) include,  

  • Catheter-Directed Thrombolysis: Using a catheter, doctors dissolve the clot with medication. 
  • Catheter-Directed Mechanical Thrombectomy: Doctors use a catheter to physically remove the clot. 
  • Thrombus Fragmentation: Doctors fragment the clot into smaller pieces that can be absorbed by the body more easily. 
  • Stent Grafting: Doctors place a stent-graft into the vein to keep it open and prevent future clots from forming. 
  • Vena Cava Filters: This procedure places a filter in the inferior vena cava, a large vein that carries blood back to the heart from the lower half of the body. 

Deep Vein Thrombosis is a dangerous condition that can leave you with severe, long-term health problems if left untreated. Understanding the symptoms and treatments associated with the condition is vital to recovery. Our expert Vascular Surgeons are here to discuss your options and find the right solution for you.