1, monitoring indicators: internationalized ratio (INR) and prothrombin time (PT). INR is the main focus. 2.Monitoring frequency: flexible according to actual patient results and ease of access. 3, monitoring requirements: national postoperative anticoagulation than the Western requirements are low, the following recommendations. Anticoagulation after aortic valve replacement alone maintains INR at 1.5-2.0; anticoagulation after mitral valve replacement alone maintains INR at 1.8-2.5; anticoagulation after combined mitral and aortic valve and/or tricuspid valve surgery maintains INR at 2.0-2.5; anticoagulation after combined atrial fibrillation or left atrial thrombosis maintains INR at 2.0-3.0. 4. Adjustment methods: (1) If INR results are within the required range, no adjustment is required. (2) If INR is lower than required, increase the warfarin dose by one-quarter or one-half tablet according to the actual situation and recheck INR after three days. (3) If INR is higher than required, reduce or stop the warfarin dose and treat with vitamin K for patients with serious bleeding risk. 5, the effect of other drugs on warfarin: If one or more of the following drugs are taken temporarily, a new, rigorous review of INR is required to readjust the dose. (1) Drugs that enhance warfarin anticoagulation are: aspirin, pautazone, hydroxypautazone, mefenamic acid, chloral hydrate, clofibrate, sulfonamides, propofol, etc.; chloramphenicol, allopurinol, monoamine oxidase inhibitors, metronidazole, cimetidine, etc.; broad-spectrum antibiotics, long-term administration of liquid paraffin or clofibrate; quinidine, thyroxine, anabolic hormones, phenelzine; chlorpromazine, diphenhydramine etc.; prothiouracil, diazoxide, propiamine, oral hypoglycemic agents, sulfopiridone, etc. (2) Drugs that weaken the anticoagulant effect of warfarin: acidophilus, light laxatives, ashwagandha, rifampicin, grumet, meprobamate, etc.; vitamin K, oral contraceptives and estrogen, etc. 6, dietary habits on warfarin: (1) food containing vitamin K will weaken warfarin anticoagulation, such as spinach, cabbage, and kelp, these foods contain a lot of vitamin K. But this does not mean that these things can not be eaten. Patients taking warfarin should keep their habits consistent and eat a fixed amount of a certain type of thing every day or week. The most taboo is to eat one day and not the next; or to eat more one day and less the next. (2) Alcohol can reduce the body’s clotting function, so patients on warfarin should avoid alcohol or limit it to 1 beer every 1-2 weeks.