What Is Venous Thromboembolism (VTE)?

Venous thromboembolism (VTE) is when a blood clot forms inside your veins. Blood clots are gel-like clumps of blood. They usually form after an injury to help stop bleeding. If blood clots form inside the veins, the clots can block the flow of blood. This can lead to serious problems.^1,2

The 2 most common types of VTE are:¹

• Deep vein thrombosis (DVT) – a blood clot that forms in a vein deep inside the body, usually in the legs, arms, or pelvis.
• Pulmonary embolism (PE) – a blood clot that blocks blood flow to the lungs.

What causes VTE?

Blood clots can form in the veins due to a few different reasons.

Veins bring blood from the organs back to the heart. Our muscles play an important role in this process. As we move around, the muscles around the deep veins contract (squeeze). This helps push the blood toward the heart. When we stay still for long periods of time, like lying in bed or sitting, the movement of blood within the veins can slow down. This increases the chances of forming blood clots.^1,2

Blood clots also form as a response to injury. For example, a physical injury or infection can damage veins. Blood clots then form around the damaged area to stop bleeding. Some people have genetic differences that make their blood more likely to clot.^1,2

When a blood clot forms in the veins, there is a chance that it can break off and move to another area. Once a blood clot enters the bloodstream, it can travel toward the heart. In many cases, the blood clot can get stuck in 1 of the arteries that supply blood to the lungs, leading to PE. When blood flow to the lungs is blocked, it can cause serious problems. In some cases, it can permanently damage the lungs and lead to death.²

Risk factors

Certain things can put you at a higher risk for developing VTE. These include:^1-3

• Staying in a hospital
• Surgery
• Inflammation
• Having VTE in the past
• Old age
• Chemotherapy
• Birth control pills

The chances of developing VTE also increase if you have another medical condition, such as:^2-4

• Cancer
• Diabetes
• Kidney disease
• High blood pressure
• Heart disease
• Inflammatory bowel disease
• Obesity

In many cases, people have more than 1 risk factor. If you have an episode of VTE, your doctor can help you identify your possible risk factors. Knowing these can also help your doctor know whether you are likely to have another episode.^2,4

Symptoms

Symptoms of DVT occur where the blood clot is formed. These can include:^1,2

• Pain
• Swelling
• Redness
• Feeling warmth near the affected area

Symptoms of PE include:^1,2

• Shortness of breath
• Chest pain
• Irregular heartbeat
• Dizziness
• Coughing up blood

Diagnosis

Your doctor will use your medical history and symptoms to determine if you might have VTE. They might also use a blood test called the D-dimer test. This test checks for a certain marker that is mostly found when the body breaks down blood clots. Imaging tests, like ultrasound or X-rays, may be used to locate the clot.²

Treatments and prevention

If you have been diagnosed with VTE, treatments are available to remove existing blood clots and stop new ones from forming. Drugs known as thrombolytics are used to break up a blood clot quickly. Blood clots in the lungs (PE) may be removed by using a thin tube (catheter) that is inserted in your veins.²

To stop new blood clots from forming, your doctor may recommend that you:²

• Exercise and move your body regularly
• Wear compression socks (they gently squeeze the legs, which improves blood flow)
• Use medicines that reduce the chances of forming a clot or blood thinners