After discharge from the hospital, in addition to regular rechecking of prothrombin time and prothrombin activity, the patient should be reviewed at the hospital for 3 months, including physical examination (listening to valve tone quality, temperature measurement, presence of murmur in the precordial region, heart rate, etc.), electrocardiogram (to clarify the presence of rhythm disturbances), echocardiogram, chest radiograph, and biochemical tests such as blood potassium, sodium, and chloride. Echocardiography showing a small amount of regurgitation of the prosthetic valve is normal. This regurgitation is purposely designed to flush the valve leaflets and prevent thrombosis when the valve is designed. 2, the condition of cardiac function, changes in heart rate and heart rhythm. 3.The presence of coughing sputum, coughing blood and dyspnea in the lungs should be noted. 4.Any bleeding phenomenon, such as bleeding gums, nose bleeding, blood in urine, black stool, etc. 5.Any embolic conditions, such as syncope, hemiparesis, aphasia, unilateral limb pain, chills or myocardial infarction. 6.The presence of sudden murmur and unexplained fever in the tone of the valve. 7.Prothrombin time and activity are controlled in a better range, with prothrombin time controlled at 18 seconds to 22 seconds and prothrombin activity controlled at 35% to 45%. 8.Maintain a certain amount of urine daily, and add digoxin and diuretics if necessary. 9. Pay attention to the presence of joint pain, redness and swelling, and to the presence of hepatomegaly and jaundice.