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Pulmonary embolism

Pulmonary embolism happens when an artery in the lung is suddenly blocked. It's usually caused by a blood clot in a leg vein that breaks loose, travels to a lung (pulmonary) artery, and blocks blood flow. This is very serious and can be deadly.

Current as of: May 1, 2026

Author: WebMD Ignite Staff

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Pulmonary embolism

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