Which of the structures in circulatory system would be most affected by a pulmonary embolism?

A pulmonary embolism is a blockage of the pulmonary artery or one of its branches by a foreign substance, most often a blood clot (thrombus), that has travelled from another part of the body. Because the pulmonary artery carries deoxygenated blood from the heart to the lungs to pick up oxygen, it affects oxygenation of blood.

The structure in circulatory system that would be most affected by a pulmonary embolism is the pulmonary artery.