Pulmonary embolism results from blockage of the pulmonary arterial tree by blood clots. It is the most common and fatal form of venous thromboembolism. Risk factors include deep vein thrombosis, pelvic vein thrombosis, heart failure, endocarditis, and atrial fibrillation. Symptoms include acute breathlessness, pleuritic chest pain, hemoptysis, dizziness, and syncope. Diagnostic tests include a D-dimer test, chest X-ray, CT scan of the chest, and MRI angiography of the whole body. Treatment options include oxygen, thrombolysis with drugs like rivaroxaban, and placement of an IVC filter. Pulmonary e