Factor V Leiden

Laboratory testing (blood tests) diagnose this disorder. Your healthcare provider may suspect you have factor V Leiden if you have a history of venous thromboembolism. They may also suspect it if one or more of your biological family members have a history of blood clots.

If your provider feels it’s warranted, they’ll order blood tests, including:

Activated protein C (APC) blood test: This coagulation factor screening test checks if your blood has resistance to activated protein C. This is a protein that prevents factor V from going into overdrive. About 9 in 10 people whose blood is resistant to protein C have the factor V Leiden mutation.
Genetic testing: If your blood is resistant to protein C, your provider will order genetic testing to check your F5 gene for the factor V Leiden mutation. In some cases, providers order this test without first ordering an APC blood test.

Simply having a family history of blood clots may not be reason enough to run these tests. Your provider will advise you on whether you need testing, as well as on the pros and cons of testing.

Symptoms

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Complications

Blood clots are a dangerous complication of atrial fibrillation (AFib). Blood clots can lead to stroke.

The risk of stroke from AFib increases as you grow older. Other health conditions also may increase the risk of a stroke due to AFib. These conditions include:

High blood pressure.
Diabetes.
Heart failure.
Some types of heart valve disease.

Blood thinners are commonly prescribed to prevent blood clots and strokes in people with atrial fibrillation.

Prevention

Healthy lifestyle choices can reduce the risk of heart disease and may prevent atrial fibrillation (AFib). Here are some basic heart-healthy tips:

Control high blood pressure, high cholesterol and diabetes.
Don't smoke or use tobacco.
Eat a diet that's low in salt and saturated fat.
Exercise at least 30 minutes a day on most days of the week unless your health care team says not to.
Get good sleep. Adults should aim for 7 to 9 hours daily.
Maintain a healthy weight.
Reduce and manage stress.

By Mayo Clinic Staff

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Diagnosis & treatment

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