The thrombus dislodged from the right upper extremity vein is mainly embolized in the pulmonary artery because the right upper extremity vein is also a reflux vein, which generally returns to the superior vena cava into the right atrium and then into the right ventricle, through which blood is pumped to the pulmonary artery, so the tethering will also occur at the pulmonary artery. It can cause sudden syncope, dyspnea, chest pain and hemoptysis, and this condition may also directly endanger life leading to sudden death. Therefore, the prevention of pulmonary embolism in right upper extremity vein thrombosis, as in other lower extremity vein thrombosis, should still include braking, prohibition of massage, and use of appropriate anticoagulants.