A pulmonary embolism is a potentially lethal occurrence in which one of the arteries leading to the lungs becomes blocked, usually by a blood clot that has migrated to that location from where it developed in a leg via a condition known as deep vein thrombosis. A patient who experiences a pulmonary embolism may display shortness of breath along with sudden chest pain and coughing that might produce bloody sputum. The condition can also cause severe sweating, skin discoloration, pain and swelling in the calves, along with an irregular heart rhythm and dizziness. Immediate medical treatment should be sought for patients experiencing these issues. Treatment may be provided in the form of anti-coagulant and clot-dissolving medications, surgery to remove a clot or installation of a vein filter.