F10 and pulmonary embolism: Apixaban belonged to an oral FXa inhibitor, which exerted an inhibitory effect on both free and clot-bound factor Xa, and also, it got approval in the clinical use of several thromboembolic disorders including reduction of stroke risk in nonvalvular atrial fibrillation, thromboprophylaxis following hip or knee replacement surgery, the treatment of deep vein thrombosis (DVT) or pulmonary embolism, and prevention of recurrent DVT and pulmonary embolism [4–6].