Pulmonary embolism

Blockage of the pulmonary artery (or one of its branches) by a blood clot, fat, air, amniotic fluid, injected talc or clumped tumor cells

Description
By far the most common form of pulmonary embolism is a thromboembolism, which occurs when a blood clot, generally a venous thrombus, becomes dislodged from its site of formation and embolizes the arterial blood supply of one of the lungs