Pulmonary embolism is caused by a blocked artery in the lungs. The most common
cause of such a blockage is a blood clot that forms in a
deep vein in the leg and travels to the lungs, where
it becomes lodged in a smaller lung artery.
Almost all blood
clots that cause pulmonary embolism are formed in the
deep leg veins. Clots also can form in the deep
veins of the arms or pelvis.
Recommended Related to Lung Disease/Respiratory Problems
A pleural effusion is an abnormal amount of fluid around the lung. Pleural effusions can result from many medical conditions. Most pleural effusions are not serious by themselves, but some require treatment to avoid problems.