Left atrial thrombus requires identification of the source of the thrombus and a decision on treatment based on the actual situation. Patients with thrombus due to infective endocarditis need anticoagulation treatment without thrombolysis, if due to mitral stenosis, etc., and in advanced stages need surgery. 1. Infective endocarditis: it can often lead to thrombus in the left atrium, which is mainly red blood cells stagnated on the platelet grid stent, and some bacteria attached. At this time there is no need for surgery, in severe cases can be thrombolysis, the general situation only need to do anticoagulation can be, can be under the guidance of the doctor to take clindamycin, aspirin, clopidogrel drugs. 2. Mitral stenosis: congenital stenosis or acquired due to heart failure and other causes of stenosis, and the degree of stenosis is serious, at this time resulting in poor thrombotic drugs, can consider anticoagulation through surgical removal of the thrombus or surgical repair of mitral stenosis, followed by if there is still embolism, and more serious, can be considered to dissolve thrombolytic therapy. Thrombolysis is risky, non-essential circumstances prohibit thrombolysis, and drug thrombolysis must be carried out under the guidance of a doctor, the daily need to test the patient’s coagulation function, in order to prevent the emergence of cerebral hemorrhage, spinal hemorrhage and other dangers.