Many patients require anticoagulation after cardiac surgery, but another problem associated with anticoagulation is bleeding, so anticoagulation needs to be controlled within a certain range to reduce the associated complications. Different procedures require different levels of anticoagulation, which are basically summarized as follows: 1. After mechanical valve replacement, oral warfarin is required for life to control INR between 2.0-2.5 2. Patients with blockers, valvuloplasty rings, and atrial defect patches need to take oral aspirin + polivir for 6 months. 5. Patients with atrial fibrillation need to take oral warfarin for life to control their INR between 2.5 and 3.0. Once, the dose should be reduced after the INR has recovered to the target value; mildly elevated INR should not even be reduced. 2. If the INR is above 5.0 and less than 9.0 without obvious bleeding, there are two ways to deal with it: one way is to stop warfarin 1 to 2 times if there are no other risk factors causing bleeding, so that the INR can be restored to the target value and the dose can be reduced orally again; if the patient has other risk factors for bleeding, he should stop warfarin once while taking VitK1 1 to 2.5 mg orally; if it is necessary to Rapid reversal of INR, such as surgery or tooth extraction, VitK1 2 to 4mg can be given orally with a view to a significant decrease in INR within 24 hours; if it is still high, VitK1 1 to 2mg can be given orally again 3. If INR exceeds 9.0 and there is no clinical bleeding, a high dose of VitK13 to 5mg should be given orally with a view to a significant decrease in INR within 24 to 48 hours; if needed, repeat Oral VitK1; if rapid reversal of INR is required or bleeding in the eye is present or the INR exceeds 20, then intravenous VitK 110 mg, supplemented with fresh frozen plasma (FFP) or prothrombin complex (PPSB) as appropriate, and the sedation may be repeated every 12 hours. If the INR is too low, gradually increase the oral dose of Warfarin under the direction of your physician.