Left atrial thrombus can be eliminated by oral warfarin. Left atrial thrombus is often seen in left atrial enlargement, the primary disease can be seen in rheumatic heart disease caused by mitral stenosis, mitral stenosis after the left atrial volume load will increase, resulting in left atrial enlargement, local blood flow is not good, resulting in the formation of thrombus, thrombus dislodgement can lead to arterial embolism. Thrombus in the left atrium should be given anticoagulant medication, commonly used oral anticoagulants are warfarin, especially for the left atrial thrombus caused by heart valve disease requires oral warfarin treatment to prevent the occurrence of arterial embolism. The main adverse reaction of warfarin is bleeding, and the color of the skin mucosa and stool should be observed during the administration of the drug. It is contraindicated in patients with active bleeding, hypersensitivity to drug components, and severe hepatic impairment. Taking warfarin requires monitoring PT-INR, and it is recommended to take it under the supervision of a physician.