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How blood clots go from good to bad

Legs in water, recognize signs and symptoms of a blood clot in the leg

Understanding Venous Thromboembolism () can help you stay ahead

Blood clots are all around

We have all seen a blood clot in action first hand. Any time you notice blood from a cut or see a bruise, it means there has been a hole in the wall of one of your blood vessels. Naturally, your body creates a protective barrier that will seal your blood vessel back off from the outside world. When you see a scab start to form, you are actually looking at a blood clot on the top of your skin.

This is why blood clots are so important; they are your body’s way of creating a protective barrier to reclose your blood vessel wall. If it wasn't for blood clots, we wouldn’t survive a simple cut or scrape.

How the clot forms, from to

What happens when your blood begins to coagulate, forming a clot? As soon as your body detects an opening in the vessel wall, are sent to the injury area and begin to form a plug. If that is not enough to stop the bleeding, your body will trigger a process called “ cascade”, which triggers millions of proteins to gather, forming strands called . weaves a web-like structure that reinforces the ’ plug. As the cascade continues to trigger formation, the clot grows. At some point you want that process to stop though, before you get too much of a good thing.

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Formation and symptoms of a

The body is meant to contain a healthy balance of proteins that both build and break down blood clots, allowing them to not only form but also to dissolve after the blood clot has served its purpose. In certain cases this balance can be thrown off, causing your body to continually produce (and thus grow) the blood clot. Want to know more about risk factors? Click here. This can become a real problem when a blood clot forms in an artery for example, or in the case of , within a “deep vein”. Deep veins are especially important because they lead directly to the body’s largest veins, called the venae cavae, which lead straight to the heart and on to your lungs.

Clot formation here is called deep vein (). typically form in the calf, thigh or pelvis / groin, although they can also appear in other locations like the arm or chest. The good news is that the condition is treatable. You can read more about key symptoms to watch out for in this article. If you believe that you may have but have not been diagnosed, you should contact your doctor.

Interested to know more? Watch our video about formation and symptoms of a

Clots that break away can create complications ()

Deep vein () can trigger pulmonary (), which can be life threatening if not treated early. Note: doctors and nurses often refer to deep venous and pulmonary together as “venous embolism” or . For a guide to all the jargon you need to know click here.

Development of a pulmonary embolism is the primary concern with . Our bodies normally handle blood clots by simply dissolving them, but if the body is unable to do this in time, a piece of the clot (called an ) could break off and begin to travel through the blood stream. Because blood pumps through our bodies in a matter of seconds, an can travel relatively fast, moving all the way up and through the right side of the heart and on to the lungs. 

A larger can end up blocking blood flow to a bigger portion of the lung, while a smaller might continue to pass down and only block a smaller portion of the lung, creating a . In both cases, the affected region in the lung is no longer able to provide oxygen to the body.

Interested to know more? Watch our video about formation and symptoms of

is a serious condition, but it is both preventable and treatable. Understanding can help reduce your risk of developing it, or letting it develop further into pulmonary embolism (). As always, contact your doctor if you have questions.


MAT 50141 Last approved April 2022

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