Anticoagulation decision-making before non-cardiac surgery in patients with mechanical heart valve: A retrospective study

OBJECTIVE: To clarify the timing of warfarin discontinuation at different ranges of INR. Improve anticoagulation management in non-cardiac surgical patients with MHV. DESIGN: This is a single-center retrospective observational study. SETTING: and participants This study used data from the Hospital Information System, and the Surgery and Anesthesia Information System of the Second Affiliated Hospital of Army Military Medical University. Participants included 121 adult patients with MHV who underwent non-cardiac surgery from 2012 to 2021. RESULTS: Overall, 121 patients with MHV (15 aortic valve only, 56 mitral valve only, and 50 with multiple valves) underwent non-cardiac surgery. When the duration of warfarin discontinuation was ≤ 3 days, 3−5 days, and≥5 days, the INR was 1.45, 1.15, and 1.09, respectively. Bleeding between INR ≤1.2 and INR >1.2 groups was not statistically significant using Student's t-test (95% CI −0.57, 0.14 P = 0.24). Multivariate regression analysis revealed that Intraoperative bleeding volume correlated with preoperative albumin levels (OR = 0.68，95% CI 0.49, 0.89). CONCLUSIONS: When need preoperative INR is less than 1.5 in patients with MHV undergoing non-cardiac surgery, preoperative warfarin discontinuation for 3 days is sufficient. If INR less than 1.2, preoperative warfarin discontinuation for 3–5 days is appropriate. And in patients with MHV underwent abdominal surgery, intraoperative bleeding is not significant reduced by lower INR after preoperative warfarin discontinuation. Furthermore, the effect of albumin levels on coagulation function cannot be ignored in patients with MHV. STRENGTHS AND LIMITATIONS: This study was derived from real-world clinical data. It's a retrospectively study to describe the INR changed according to the duration of warfarin discontinuation in patients with MHV and compared intraoperation of bleeding volume between INR>1.2 and INR ≤ 1.2after warfarin discontinuation. To clarify the timing of warfarin discontinuation at different ranges of INR. Improve anticoagulation management in non-cardiac surgical patients with MHV, while providing clinicians with a reference for preoperative warfarin adjustment. This study does have a few limitations. The number of cases is small because patients undergoing repeat noncardiac surgery after heart valve surgery are a special case population. And the patients were not followed up after non-cardiac surgery. The impact of changes in INR on postoperative complications could not be assessed in patients with MHV.