How are blood clots formed?

Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
A blood clot, also known as a thrombus, is formed when particles in your blood combine to form a solid piece of matter. A blood clot usually consists of platelets, fibrin, and other components. They usually form for your benefit -- to stop bleeding after a cut or scrape. However, blood clots can form in situations that don’t involve a cut at all. Long periods of inactivity or damage to an arterial wall can also form a clot. An embolus is a traveling, broken-off piece of a thrombus. As it travels, it eventually degrades. However, if it travels through a more narrow passageway and gets stuck, the consequences can be deadly.
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A normal, regular heartbeat keeps blood flowing steadily through the heart, brain and the rest of the body. When the heart’s atrial chambers stop pumping in an organized rhythm, blood tends to stagnate and blood clots can form.

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