Pulmonary embolism. Bill had a blood clot in his leg that broke loose and traveled to his lung where it is blocking an artery.
Pulmonary embolism is a blockage in one of the pulmonary arteries in your lungs. In most cases, pulmonary embolism is caused by blood clots that travel to the lungs from the legs or, rarely, other parts of the body (deep vein thrombosis).