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Blood clotting is the body’s way of preventing excessive bleeding when a blood vessel is injured.
Typically, the body will dissolve the clot after the injury has healed,the American Society of Hematology says.
But occasionally, a clot forms despite no obvious injury to a vessel, or the clot doesn’t dissolve on its own. This can pose the dangerous possibility of limiting oxygenated blood to tissues and organs such as the heart or lungs.
Or a clot may impede the flow of deoxygenated blood back to the heart.