What is a pulmonary embolism (PE)?

A pulmonary embolism (PE) is specifically defined as the blocking of a pulmonary artery due to a blood clot. This blood clot often originates from another part of the body, commonly from the deep veins of the legs, and travels to the lungs. The obstruction can significantly reduce or completely block blood flow to the lung tissue, leading to serious complications such as decreased oxygen levels in the blood and strain on the heart.

Recognizing the correct definition is crucial, as it highlights the clinical implications of a PE, including symptoms like sudden shortness of breath, chest pain, and rapid heart rate, which require immediate medical attention. Understanding the nature of a PE is essential for effective diagnosis and treatment, differentiating it from other respiratory conditions that may involve fluid, infection, or inflammation.