Analysis Of Current Status Of Anticoagulant Therapy In Patients With Non-valvular Atrial Fibrillation

Background and objective:Atrial fibrillation（AF）is one of the most common arrhythmias.The risk of ischemic stroke in AF patients without anticoagulant therapy increases 5 times.Ischemic stroke is the most common cause of disability and death in AF patients,it also has seriously negative impacts on the quality of life and prognosis of patients.Therefore,anticoagulant therapy for AF patients is very important.According to the etiology,AF can be divided into valvular atrial fibrillation（VAF）and non-valvular atrial fibrillation（NVAF）.At present,the anticoagulant effect of warfarin has been widely recognized.Four large-scale randomized controlled trials（RCTs）of the new oral anticoagulants（NOACs）showed that NOACs were not inferior to warfarin in preventing thromboembolic events in NVAF patients,but they were safer than warfarin.Compared with non-Asian patients,Asian NVAF patients were more likely to have intracranial hemorrhage when taking warfarin.However,only 10%of Asian patients included in the previous RCTs,and there were few real-world data comparing the efficacy of oral anticoagulants in Asian NVAF patients.Therefore,this study retrospectively analyzed the current status of anticoagulant therapy in NVAF patients,and compared the effectiveness and safety of different treatments.The aim of this study was to provide some references for the choice of anticoagulant therapy in NVAF patients.Method:We reviewed the records of NVAF patients who were hospitalized in the Cardiovascular Department of Jinling Hospital from January 2016 to January 2020.According to the therapy,the enrolled patients were divided into non-anticoagulation group and anticoagulation group,which included warfarin group,dabigatran group and rivaroxaban group.The dabigatran group and rivaroxaban group were collectively referred to as the NOACs group.CHA₂DS₂-VASc score and HAS-BLED score were used respectively to assess the risk of thromboembolism and bleeding in all enrolled patients.The thromboembolic and bleeding events of the patients above after discharge were followed up.The clinical data above were analyzed statistically with t test,X₂test and Fisher’s exact probability test.Results:1.A total of 457 cases of NVAF patients who met the inclusion criteria were enrolled,of which 349 cases（349/457,76.4%）were in the anticoagulation group and 108 cases（108/457,23.6%）were in the non-anticoagulation group.In the anticoagulation group,72 cases were in the warfarin group（72/349,20.6%）,277 cases were in the NOACs group（277/349,79.4%）.In the NOACs group,166 cases were in the dabigatran group（166/277,59.9%）,111 cases were in the rivaroxaban group（111/277,40.1%）.2.Among 457 NVAF patients,63 cases were in the low risk of thromboembolism group（63/457,13.8%）,and 394 cases were in the medium-high risk of thromboembolism group（394/457,86.2%）.Among the medium-high risk of thromboembolism group,294 cases（294/394,74.6%）received anticoagulant therapy,but rest 100 cases（100/394,25.4%）did not.3.Among 457 NVAF patients,354 cases were in the low risk of bleeding group（354/457,77.5%）,and 103 cases were in the high risk of bleeding group（103/457,22.5%）.In the low risk of bleeding group,274 cases received anticoagulant therapy（274/354,77.4%）,and 80 cases（80/354,22.6%）were not treated with anticoagulation.4.The rate of thromboembolic events in anticoagulation group was significantly lower than that in non-anticoagulation group（6.0%vs.31.5%,P<0.01）,and the rate of thromboembolic events in dabigatran group was lower than that in rivaroxaban group（3.6%vs.9.9%,P<0.05）.However,there was no significant difference between NOACs group and warfarin group in the rate of thromboembolic events（6.1%vs.5.6%,P>0.05）.5.The rate of bleeding events in anticoagulation group was significantly higher than that in non-anticoagulation group（5.4%vs.0%,P<0.01）,and the rate of bleeding events in NOACs group was lower than that in warfarin group（3.2%vs.13.9%,P<0.05）.There was no significant difference between dabigatran group and rivaroxaban group（2.4%vs.4.5%,P>0.05）.Conclusion:1.Anticoagulant therapy for NVAF patients with the medium-high risk of thromboembolism could significantly reduce the incidence of thromboembolic events.2.NOACs were not inferior to warfarin in preventing thromboembolic events in NVAF patients,but NOACs caused less bleeding than warfarin in this study.3.Coagulation function monitoring was generally not enough in NVAF patients with warfarin,which might be related to the events of thromboembolic and bleeding,which suggested that coagulation function monitoring should be strengthened much more when warfarin was used.4.There was no significant difference in the incidence of bleeding between dabigatran group and rivaroxaban group,but the rate of thromboembolism in dabigatran group was lower than that in rivaroxaban group,which might be related to the generally low dose of rivaroxaban used in this study.Therefore,for NVAF patients with medium-high risk of thromboembolism,it was recommended to strictly follow the recommended dose of the guidelines if rivaroxaban was selected for anticoagulation.