Pulmonary embolism occurs when a clump of material, most often a blood clot, gets wedged into an artery in your lungs. These blood clots most commonly originate in the deep veins of your legs, but they can also come from other parts of your body. This condition is known as deep vein thrombosis (DVT).

Occasionally, other substances can form blockages within the blood vessels inside your lungs. Examples include:

  • Fat from within the marrow of a broken long bone
  • Part of a tumor
  • Air bubbles

It's rare to have a single pulmonary embolism. In most cases, multiple clots are involved. The lung tissue served by each blocked artery is robbed of blood and may die. This makes it more difficult for your lungs to provide oxygen to the rest of your body.

Jan. 02, 2014

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