A Follow-up Study On Anticoagulation Complications After Bioprosthetic Heart Valve Replacement

Objective: In this study,the clinical status and anticoagulant complications of warfarin use in patients undergoing bioprosthetic valve replacement in Qingdao area were followed up in the early postoperative period(3 months after operation).To compare and analyze the early postoperative anticoagulant complications between patients with cardiovascular risk factors and patients without cardiovascular risk factors,and to explore the efficacy and safety of postoperative routine anticoagulant therapy in patients with cardiovascular risk factors.The complications of different anticoagulant regimens in the late postoperative period(3 months to 1 year after peration)were further observed in patients with atrial fibrillation,which provided a guidance for long-term anticoagulant therapy in patients with atrial fibrillation after bioprosthetic valve replacement.Methods: 856 patients undergoing cardiac bioprosthetic valve replacement in the affiliated Hospital of Qingdao University Medical College from January 2014 to December 2017 were followed up.The general data,atrial fibrillation,anticoagulant regimen,anticoagulation related bleeding events,thromboembolism events and death were recorded.856 patients were divided into non-atrial fibrillation group and atrial fibrillation group according to the presence or absence of atrial fibrillation.The patients without AF were further divided into two groups,group A(without cardiovascular risk factors)and group B(with cardiovascular risk factors)according to the presence or absence of cardiovascular high risk factors(hypertension,diabetes,previous TIA or stroke).The patients with AF were further divided into three groups,group C(warfarin),group D(aspirin)and group E(warfarin + aspirin)according to the different anticoagulant regimens in the late postoperative period(3 months to 1 year after operation).The anticoagulation related bleeding events,thromboembolic events and death in the early postoperative period were analyzed and compared between the Group A and Group B in patients without AF.The anticoagulant related bleeding events,thromboembolic events and death in the late postoperative period(3 months to 1 yearafter operation)were analyzed and compared among the Group C,Group D and Group E in patients with AF.Results: A total of 894 cases of cardiac bioprosthetic valve replacement were collected and 852 cases were followed up with the follow-up rate was 95.30%(852/894).Including 476 cases in the non-atrial fibrillation group and 376 cases in the atrial fibrillation group.There were 15 cases(3.15%)of anticoagulation-related thromboembolism,28 cases(5.88%)of bleeding and 7 cases(1.47%)of death in the non-atrial fibrillation group.In group A(without cardiovascular risk factors,n=272),anticoagulation-related thromboembolism occurred in 4 cases(1.47%),bleeding in 15cases(5.51%)and death in 1 case(0.37%).There were 11 cases(5.39%)of anticoagulant-related thromboembolism and 13 cases(6.37%)of bleeding and 6 cases(2.94%)of death in group B(with cardiovascular risk factors,n=204).The incidence of thromboembolism and mortality in group B were higher than those in group A,and there was significant difference between the two groups(P <0.05),but there was no significant difference in the incidence of bleeding between the two groups(P>0.05).In AF group,anticoagulation-related thromboembolism occurred in 16 cases(4.26%),bleeding in 21cases(5.59%)and death in 9 cases(2.39%).In group C(warfarin,n=182),anticoagulant-related thromboembolism occurred in 7 cases(3.85%),bleeding in 10 cases(5.49)and death in 2 cases(1.10%).In group D(aspirin,n=108),anticoagulant thromboembolism occurred in 9 cases(8.33%),bleeding in 6 cases(5.56%)and death in6 cases(5.56%).In group E(warfarin + aspirin,n=86),anticoagulant related hemorrhage occurred in 5 cases(5.81%),death in 1 case(1.16%),and no thromboembolism occurred.There were significant differences in the incidence of thromboembolism and mortality among the three groups(P<0.05).The incidence of thromboembolism and mortality were the highest in group D,and no thromboembolism occurred in group E.Conclusion: For non-atrial fibrillation patients with cardiovascular risk factors,the incidence of thromboembolism and mortality were higher in the early stage(3 months after operation)after cardiac bioprosthetic valve replacementand with the current anticoagulant regimen and intensity of anticoagulant therapy in our hospital.It is suggested that appropriate enhanced anticoagulant therapy is needed for patients withcardiovascular risk factors.However,specific anticoagulant regimen still need to be further explored.For patients with atrial fibrillation undergoing bioprosthetic valve replacement,warfarin anticoagulant therapy or low-dose aspirin combined with warfarin anticoagulant therapy in the late postoperative period(3 months to 1 year after operation)can significantly reduce the incidence of thromboembolism and mortality.And combined anticoagulant therapy did not increase the risk of bleeding in patients with atrial fibrillation.However,the therapeutic effect of aspirin alone is poor,and the incidence of thromboembolicsm and mortality are the highest among the three groups.