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How can a blood clot in a leg vein become a pulmonary embolism?
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bleeding and blood clotting
Red blood cells (erythrocytes) trapped in a mesh of fibrin threads. Fibrin, a tough, insoluble protein formed after injury to the blood vessels, is an essential component of blood clots.
A blood clot in a leg vein, known as deep vein thrombosis (DVT), can lead to a pulmonary embolism when a portion of the clot breaks off from the vein wall.1
Once detached, this fragment travels through the circulatory system and enters the blood vessels leading to the lungs. The clot eventually reaches a pulmonary artery or one of its branches that is too narrow for it to pass through, resulting in an embolismβa blockage that obstructs normal blood flow to the lungs. This is a serious medical condition that requires prompt diagnosis and treatment to prevent further complications.21