Pulmonary embolism is sudden blockage of blood flow in an artery in the lung. The blockage (an embolus) can be caused by a blood clot, tumor, amniotic fluid, or fat in the artery.

Blood clots in the deep veins of the leg are the most common cause of pulmonary embolism. A clot may break loose from a deep vein in the leg and travel to a pulmonary artery in the lung, where it can block blood flow.

Pulmonary embolism can be a very serious condition that can result in death. Symptoms of a pulmonary embolus include:

• Sudden, sharp chest pain.
• Shortness of breath.
• Chest pain that gets worse with deep breathing or coughing.
• Coughing up blood or pink, foamy mucus.
• Rapid heart rate.
• Sweating.
• Anxiety.

Pulmonary embolism is treated in the hospital with monitoring, oxygen, and anticoagulants to prevent more blood clots.