Venous Thromboembolism Causes and Risk Factors
What causes venous thromboembolism (VTE)?
VTE occurs in the veins that carry blood to your heart. Blood clots can develop in veins damaged by surgery or trauma, or they can develop as a result of caused by an infection or injury.
Deep vein thrombosis (DVT) may occur if the flow of blood slows down in the veins, or something damages the blood vessel lining. Pulmonary embolism (PE) refers to an from a deep vein blood clot or a blood vessel in the lungs that breaks loose and travels to the lungs, blocking an in the lung.
What raises the likelihood of VTE?
Most often, there is more than one risk factor involved. The more risk factors you have, the greater the chance you have of developing VTE.
Not moving for long periods of time
Being still slows blood flow through the veins in your arms and legs, raising the likelihood of DVT. Especially when combined with other risk factors, DVT can develop during a long flight (more than 4 hours) or when a person is on bed rest in a nursing home, hospital setting, or after surgery. The chance of developing a blood clot is highest in the first 3 months after surgery and lowers with time. Ask your healthcare provider about prevention plans if you are scheduled for major surgery. Slower blood flow can create a low- environment that traps blood in places such as the leg veins or makes it easier for clots to form.
Learn about ways to prevent blood clots after surgery or while traveling.
Certain medical conditions can raise your chance of developing VTE. Some conditions are more closely linked to developing DVT or pulmonary embolism than others and include:
- Blood clotting disorders or a history of blood clots
- and cancer treatments including chemotherapy and surgery
- heart attack or congestive heart failureHeart conditions such as
- High blood pressure, which can damage blood vessels
- Infections, such as with SARS-CoV-2, the virus that causes COVID-19
- Kidney disease which makes the blood clot more easily
- Spinal cord injury, which can damage veins deep in your body and may cause paralysis, reducing blood flow
- Obesity, which can lead to and damage in the lining of blood vessels
VTE can occur at any age, but your chance goes up as you age. The chance of VTE nearly doubles every 10 years after age 40.
Your family history can affect your chances of developing VTE. Researchers have found dozens of mutations (changes in the structures of your ) that can raise your chance of VTE. Some changes make your blood more likely to clot. If your parents have these genetic changes, you may have inherited them.
Studies show that the likelihood of VTE among the siblings of someone who has had VTE is more than double the likelihood among the general population.
Before menopause, women are more likely to get VTE compared to men. After menopause, the likelihood of VTE is higher in men.
Learn more about VTE and women.