Pulmonary Embolism

         Basic Facts

  • The pulmonary arteries and their branches carry blood from the heart to the lungs to be oxygenated.
  • A pulmonary embolism is the blockage or closure of a pulmonary artery or one of its branches by an abnormal object, most frequently a blood clot. The clot typically travels with the flow of blood from a leg vein to the site where it creates a blockage.
  • When a pulmonary artery becomes severely blocked, blood oxygen levels fall, and blood pressure in the lungs and pulmonary arteries can rise so high that the heart may not be able to pump enough blood out of its chambers.
VM Pulmonary Embolism
A pulmonary embolism occurs when an embolus, or abnormal object, moves through the circulatory system and blocks an artery in the lung. Because about 10 percent of pulmonary embolisms are fatal within the first hour after onset of symptoms, prompt diagnosis and treatment are critical.

If a blockage occurs in a large blood vessel or if the person suffers from another pulmonary condition, such as pulmonary hypertension, the blockage could cause pulmonary infarction, which means lung tissue death. 

Pulmonary Embolism FAQ