Pulmonary embolism blocks which vessel?

Pulmonary embolism blocks which vessel?

• A. The lung's main artery
• B. The aorta
• C. The coronary artery
• D. The pulmonary veins

Answer: (A)

Pulmonary embolism blocks the vessels that carry blood from the right side of the heart to the lungs—the pulmonary arteries. An embolus traveling from the veins lodges in these arteries, obstructing blood flow to portions of the lung and causing a mismatch between ventilation and perfusion. The other listed vessels aren’t the site of a PE: the aorta is the main artery of systemic circulation, a blockage there would affect the whole body; the coronary artery supplies the heart muscle, and its blockage causes a heart attack; the pulmonary veins return oxygenated blood from the lungs to the left atrium, and are not the typical site of obstruction in a pulmonary embolism.

Pulmonary embolism blocks the vessels that carry blood from the right side of the heart to the lungs—the pulmonary arteries. An embolus traveling from the veins lodges in these arteries, obstructing blood flow to portions of the lung and causing a mismatch between ventilation and perfusion. The other listed vessels aren’t the site of a PE: the aorta is the main artery of systemic circulation, a blockage there would affect the whole body; the coronary artery supplies the heart muscle, and its blockage causes a heart attack; the pulmonary veins return oxygenated blood from the lungs to the left atrium, and are not the typical site of obstruction in a pulmonary embolism.