Low Intensity Anticoagulation In On-X Mechanical Aortic Valve Application Study After Changing The Surgery

Objective:To explore the safety and efficacy of low-intensity anticoagulation in patients undergoing On-X mechanical aortic valve replacement in Sichuan province,and expect to reduce postoperative anticoagulation-related adverse events,improve patient prognosisandimprovepatientqualityoflife.Methods:Thisstudyretrospectivelycollecteddataonpatientsdiagnosedwithaortic valve disease(stenosis or closure insufficiency)and who underwent surgical on-X mechanical aortic valve replacement between December 2018 and December 2021,after warfarin anticoagulation and regular review,the International Standardized Ratio(INR)was chosen to adjust the warfarin dose,the INR targets in our center range from 1.5-2.5,the intensity of warfarin anticoagulation and absence of bleeding or thromboembolism within1 year by telephone,wechat and outpatient follow-up,and in the regular postoperative review of the heart color ultrasound,understand the presence of paravalvular leakage,valve thrombosis and infectious endocarditis.According to the stable INR value(relatively stable INR average within 3 consecutive months after surgery),patients were divided into low-intensity anticoagulant group(INR:1.5-2.0)and high-intensity anticoagulant group(INR:2.0-2.5),comparetheincidenceofanticoagulation-relatedadverseeventsbetweenthe two groups,and explore the appropriate anticoagulation intensity after On-x mechanical aorticvalvereplacement.Results:According to the inclusion and exclusion criteria,a total of 104 patients were included in the study,all patients underwent smoothly and received warfarin anticoagulation,with 53 patients included in the low-intensity group(INR1.5-2.0)and 51 patients included in the higher-intensity group(2.0-2.5).(1)All patients shown in Table 2include other intraoperative procedures except aortic valve replacement,including aortic valve vegetation removal,mitral valvuloplasty and tricuspid valvuloplasty;(2)Table 3shows the patients in both groups in gender,age,BMI,underlying diseases(hypertension,diabetes mellitus and coronary heart disease),valvular disease etiology and pathology,cardiac function grade(NYHA)and other indicators(P>0.05);(3)As shown in Table 4,there was no significant difference in the two groups in surgical parameters,including replacement valve size,cardiopulmonary bypass time,aortic block time,and ICU stay(P>0.05);(4)Review of heart color ultrasound found that 3 patients had paravalvular leakage,all were cured by surgery;table 5 shows that we selected 57 patients from 104 patients who were reviewed in our hospital during 3-6 months and 9-12 months and had complete follow-up data,and compare the cardiac color ultrasound related indicators of these patients in the two time periods,the results indicate that the end-systolic diameter,aortic valve pressure difference and left ventricular ejection fraction are significantly different(P<0.05);(5)Table 6 shows a statistically significant PT,INR and anticoagulant bleeding adverse events(P<0.05),however,there was no significant differenceinanticoagulantthromboembolismadverseevents(P>0.05).Conclusion:For patients who need On-X mechanical aortic valve replacement and have no risk factors for thromboembolism,the main problem of anticoagulation therapy is prone to bleeding adverse events.It is feasible to appropriately reduce the anticoagulation intensity.It is appropriate to control the INR target range to 1.5-2.0,which can reduce the incidence of bleeding adverse events,significantly improve the prognosis of patients and improvethequalityoflifeofpatients.