Oral anticoagulants play an important role in the prevention and treatment of thromboembolic diseases.Warfarin,a traditional oral anticoagulant,is limited in clinical use due to its limitations such as narrow therapeutic window and requirements on frequent monitoring and dose adjustment.Direct oral anticoagulants(DOACs)such as dabigatran,rivaroxaban,apixaban,and edoxaban are increasingly used to prevent and treat venous thrombosis or thrombus formation.However,recent studies have documented inter-individual variability in plasma drug levels of DOACs.This article summarizes the recent advances in the pharmacogenomics of DOACs.
Administration, Oral ; Anticoagulants ; therapeutic use ; Atrial Fibrillation ; drug therapy ; Dabigatran ; Pharmacogenetics ; Rivaroxaban

BACKGROUND: Aspirin has demonstrated safety and efficacy for venous thromboembolism (VTE) prophylaxis following total hip arthroplasty (THA); however, inconsistent dose regimens have been reported in the literature. This study aimed to evaluate and compare the safety and efficacy of 100 mg aspirin twice daily with rivaroxaban in VTE prophylaxis following THA. METHODS: Patients undergoing elective unilateral primary THA between January 2019 and January 2020 were prospectively enrolled in the study and randomly allocated to receive 5 weeks of VTE prophylaxis with either oral enteric-coated aspirin (100 mg twice daily) or rivaroxaban (10 mg once daily). Medication safety and efficacy were comprehensively evaluated through symptomatic VTE incidence, deep vein thrombosis (DVT) on Doppler ultrasonography, total blood loss (TBL), laboratory bloodwork, Harris hip score (HHS), post-operative recovery, and the incidence of other complications. RESULTS: We included 70 patients in this study; 34 and 36 were allocated to receive aspirin and rivaroxaban prophylaxis, respectively. No cases of symptomatic VTE occurred in this study. The DVT rate on Doppler ultrasonography in the aspirin group was not significantly different from that in the rivaroxaban group (8.8% vs. 8.3%, χ2 = 0.01, P = 0.91), confirming the non-inferiority of aspirin for DVT prophylaxis (χ2 = 2.29, P = 0.01). The calculated TBL in the aspirin group (944.9 mL [658.5-1137.8 mL]) was similar to that in the rivaroxaban group (978.3 mL [747.4-1740.6mL]) (χ2 = 1.55, P = 0.12). However, there were no significant inter-group differences in HHS at post-operative day (POD) 30 (Aspirin: 81.0 [78.8-83.0], Rivaroxaban: 81.0 [79.3-83.0], χ2 = 0.43, P = 0.67) and POD 90 (Aspirin: 90.0 [89.0-92.0], Rivaroxaban: 91.5 [88.3-92.8], χ2 = 0.77, P = 0.44), the incidence of bleeding events (2.9% vs. 8.3%, χ2 = 0.96, P = 0.33), or gastrointestinal complications (2.9% vs. 5.6%, χ2 = 1.13, P = 0.29). CONCLUSION: In terms of safety and efficacy, the prophylactic use of 100 mg aspirin twice daily was not statistically different from that of rivaroxaban in preventing VTE and reducing the risk of blood loss following elective primary THA. This supports the use of aspirin chemoprophylaxis following THA as a less expensive and more widely available option for future THAs. TRIAL REGISTRATION Chictr.org, ChiCTR18000202894; http://www.chictr.org.cn/showproj.aspx?proj=33284.
Anticoagulants ; Arthroplasty, Replacement, Hip/adverse effects* ; Arthroplasty, Replacement, Knee ; Aspirin/therapeutic use* ; Humans ; Rivaroxaban/therapeutic use* ; Venous Thromboembolism/prevention & control*

INTRODUCTIONDirect oral anticoagulants (DOACs) are establishing themselves as principle choices for the treatment of a variety of thrombotic disorders. DOACs are also known to affect common coagulation tests which are routinely performed for patients in clinical practice. An understanding of their varied effects is crucial for the appropriate ordering of coagulation tests and their interpretation.

MATERIALS AND METHODSLaboratories in public and private healthcare institutions and commercial sectors were surveyed on coagulation tests offered and their methods. A Medline and bibliography search, including a search on search engines, was performed for publications reporting the effects of dabigatran, apixaban and rivaroxaban on these coagulation tests. These papers were reviewed and summarised for consensus recommendations.

RESULTSProthrombin time (PT) and activated partial thromboplastin time (aPTT) are variably affected by the DOACs and dependent of the coagulation assays used. Clinicians must know which laboratory has performed these tests to logically interpret test results. A normal PT or aPTT does not exclude the presence of residual DOACs effect. The thrombin time is sensitive to dabigatran but not apixaban or rivaroxaban. Specialised coagulation tests such as thrombophilia tests are also variably affected by the DOACs. All laboratories in Singapore however, employ similar test methods permitting a common set of recommendations for specialised coagulation testing.

CONCLUSIONKnowledge of the effects of DOACs on coagulation testing is essential to determine the appropriateness of performing such tests and interpreting them coherently. Practical recommendations which are tests and location-specific are set out in this paper.

Antithrombins ; therapeutic use ; Blood Coagulation Tests ; Dabigatran ; therapeutic use ; Factor Xa Inhibitors ; therapeutic use ; Humans ; Partial Thromboplastin Time ; Practice Guidelines as Topic ; Prothrombin Time ; Pyrazoles ; therapeutic use ; Pyridones ; therapeutic use ; Rivaroxaban ; therapeutic use ; Singapore

INTRODUCTIONThis study aimed to compare medication adherence and treatment persistence of patients on warfarin versus rivaroxaban in Singapore. A secondary objective was to identify significant covariates influencing adherence.

MATERIALS AND METHODSA retrospective cohort study was conducted where data from September 2009 to October 2014 was retrieved from the hospital electronic databases. Prescription records of rivaroxaban patients with 3 months or more of continuous prescription were extracted and compared against those of patients on warfarin. Primary outcome of adherence was determined based on the medication possession ratio (MPR), while treatment persistence was determined by outpatient clinic appointment gaps.

RESULTSA total of 94 rivaroxaban and 137 warfarin users were analysed by complete case analysis. The MPR of warfarin patients was lower than rivaroxaban patients by 10% (95% CI, 6.4% to 13.6%; P <0.0001). Also, there were more warfarin patients who had gaps in treatment persistence compared to those prescribed rivaroxaban (8.0% vs 1.1%; P = 0.03). Significant factors affecting medication adherence were age and duration of anticoagulant use. For every 10-year increase in age, MPR increased by 1.7% (95% CI, 0.7% to 2.8%). Similarly, for every year increase in duration of use, MPR increased by 1.8% (95% CI, 0.6% to 3.0%). Race, gender, concomitant medication and type of residence were not found to be significant covariates in the multivariable analysis.

CONCLUSIONPatients on rivaroxaban are likely to be more adherent to their prescribed oral anticoagulant with increasing age and duration of treatment influencing adherence.

Adult ; Age Factors ; Anticoagulants ; therapeutic use ; Databases, Factual ; Factor Xa Inhibitors ; therapeutic use ; Female ; Humans ; Male ; Medication Adherence ; statistics & numerical data ; Middle Aged ; Pulmonary Embolism ; drug therapy ; Retrospective Studies ; Rivaroxaban ; therapeutic use ; Singapore ; Venous Thrombosis ; drug therapy ; Warfarin ; therapeutic use

OBJECTIVETo evaluate the efficacy and safety of three antithrombotic agents on venous thromboembolism (VTE) after unilateral total knee arthroplasty.

METHODSFrom November 2011 to March 2014, 149 patients undergoing unilateral total knee arthroplasty for knee osteoarthritis were reviewed. Among them, there were 66 males and 83 females, ranging in age from 48 to 76 years old. All the cases were randomly divided into three groups including Aspirin group, low-molecular-weight heparin (LMWH) group, and rivaroxaban group, according to antithrombotic agents. Deep vein thrombosis (DVT), pulmonary embolism (PE) and bleeding complication (including wound ecchymosis, hematoma and other local complications, gastrointestinal, cardiovascular, urinary hemorrhage and other major bleeding events) of antithrombotic agents were observed and analyzed statistically at the 6 week, 8 week, and 12 week after operation.

RESULTSAmong patients who received Aspirin (48 cases), 4 patients had DVT, in 1 patient had PE, and 2 patients had bleeding complication. Among 54 patients in low-molecular-weight heparin group, 3 patients had DVT, 1 patient had PE, and 3 patients had bleeding complication. While among those patients received the rivaroxaban (47 cases), 3 patients had DVT, 0 patient had PE, and 11 patients had bleeding complication. There were no statistically differences among three groups on DVT, and PE (P>0.05). The incidence of bleeding complication in rivaroxaban group was higher than the other two antithrombotic agents, and the difference among the three groups was statistically significant (P<0.05).

CONCLUSIONAspirin, low-molecular-weight heparin, and rivaroxaban could effectively reduce the incidence of VTE after total knee arthroplasty, and their efficacy was similar. Rivaroxaban has a higher incidence of bleeding complication and further clinical trials are required to be conducted to assess the safety of rivaroxaban in clinical.

Aged ; Arthroplasty, Replacement, Knee ; adverse effects ; Aspirin ; therapeutic use ; Case-Control Studies ; Female ; Fibrinolytic Agents ; therapeutic use ; Heparin, Low-Molecular-Weight ; therapeutic use ; Humans ; Male ; Middle Aged ; Postoperative Complications ; prevention & control ; Rivaroxaban ; therapeutic use ; Venous Thromboembolism ; prevention & control

Objective: This analysis was performed to evaluate the efficacy and the safety of rivaroxaban-aspirin combination therapy in secondary prevention of major adverse cardiovascular events in Chinese patients enrolled in the COMPASS trial. Methods: COMPASS was a prospective, international multi-center and randomized controlled trial. From September 2014 to February 2017, 1 086 patients with stable coronary artery disease and peripheral artery diseases were recruited from 31 centers in China. Patients were randomly assigned to separately receive the therapy of rivaroxaban (2.5 mg twice a day) plus aspirin (100 mg once a day,) group (n=366), rivaroxaban (5 mg twice a day) alone group (n=365), and aspirin (100 mg once a day) alone group (n=355). Baseline information such as age, sex, etc. of all three groups was collected. Finally, 1 081 patients were followed up successfully, with the follow-up rate 99.5% and the average follow-up time was 19 months. The primary efficacy endpoint was the composite of cardiovascular death, myocardial infarction and stroke. The primary safety endpoint was major bleeding evaluated by modified International Society on Thrombosis and Haemostasis criteria. Results: Age of patients was (64.2±8.3) years and there were 293 male in rivaroxaban plus aspirin group. Age of patients was (63.8±9.0) years, and there were 301 male patients in rivaroxaban alone group. Age of patients was (63.6±8.8) years, and there were 282 male patients in the aspirin alone group. The incidences of primary efficacy endpoint occurred in 9 cases (1.5%) in rivaroxaban with aspirin group, 21 cases (3.7%) in rivaroxaban alone group and 14 cases (2.5%) in aspirin alone group. Meanwhile, the incidences of primary safety endpoint occurred in 6 cases (1.0%) in rivaroxaban with aspirin group, 9 cases (1.6%) in rivaroxaban alone group and 7 cases (1.2%) in aspirin alone group. The net clinical benefit events were 10 cases (1.7%) in rivaroxaban with aspirin group, 22 cases (3.9%) in rivaroxaban alone group and 15 cases (2.7%) in aspirin alone group (P>0.5%). Conclusions: The combination of rivaroxaban with aspirin can be safe and effectively used for the secondary prevention in Chinese patients with stable coronary artery disease and peripheral artery diseases.
Aged ; Aspirin/therapeutic use* ; Cardiovascular Diseases/prevention & control* ; China ; Drug Therapy, Combination ; Factor Xa Inhibitors/therapeutic use* ; Female ; Humans ; Male ; Middle Aged ; Platelet Aggregation Inhibitors/therapeutic use* ; Prospective Studies ; Rivaroxaban/therapeutic use* ; Secondary Prevention

OBJECTIVETo study the effect of autologous drained blood reinfusion on hidden blood loss and limb swelling following rivaroxaban anticoagulation for primary total hip arthroplasty.

METHODSFrom May, 2011 to October, 2012, 98 patients undergoing primary unilateral total hip arthroplasty received rivaroxaban therapy for prevention of deep venous thrombosis (DVT). Forty-five of the patients used a drained blood reinfusion device (group A) and 53 patients did not (group B). Hidden blood loss and the maximal changes of postoperative circumferential length of the mid-thigh were measured and compared between the two groups.

RESULTSThe mean total blood loss, the hidden blood loss, and the maximal changes of postoperative thigh circumference were 1591.1∓337.3 ml, 1591.1∓337.3 ml, and 5.1∓2.8 cm in group A, as compared to 1374.5∓317.3 ml, 467∓96.8 ml, 3.9∓1.4 cm in group B, respectively. The two groups showed a significant difference in the maximal changes of postoperative mid-thigh circumference (P<0.01) but not in hidden blood loss (P>0.05).

CONCLUSIONReinfusion of autologous drained blood does not affect hidden blood loss but can increase limb swelling following primary total hip arthroplasty with rivaroxaban anticoagulation.

Adult ; Aged ; Aged, 80 and over ; Anticoagulants ; therapeutic use ; Arthroplasty, Replacement, Hip ; adverse effects ; Blood Loss, Surgical ; Blood Transfusion, Autologous ; methods ; Edema ; etiology ; Female ; Humans ; Male ; Middle Aged ; Morpholines ; therapeutic use ; Rivaroxaban ; Thiophenes ; therapeutic use ; Venous Thrombosis ; prevention & control

Aged ; Aged, 80 and over ; Anticoagulants ; therapeutic use ; Aspirin ; therapeutic use ; Atrial Fibrillation ; complications ; drug therapy ; Brain Ischemia ; etiology ; prevention & control ; Dabigatran ; therapeutic use ; Dipyridamole ; therapeutic use ; Female ; Guideline Adherence ; statistics & numerical data ; Humans ; Male ; Middle Aged ; Platelet Aggregation Inhibitors ; therapeutic use ; Practice Guidelines as Topic ; Primary Prevention ; statistics & numerical data ; Pyrazoles ; therapeutic use ; Pyridones ; therapeutic use ; Rivaroxaban ; therapeutic use ; Stroke ; etiology ; prevention & control ; Ticlopidine ; analogs & derivatives ; therapeutic use ; Warfarin ; therapeutic use

Cirrhosis can occur with the development of portal vein thrombosis (PVT). PVT may aggravate portal hypertension, and it can lead to hepatic decompensation. The international guideline recommends for anticoagulation treatment to be maintained for at least 3 months in all patients with acute PVT. Low-molecular-weight-heparin and changing to warfarin is the usual anticoagulation treatment. However, warfarin therapy is problematic due to a narrow therapeutic window and the requirement for frequent dose adjustment, which has prompted the development of novel oral anticoagulants for overcoming these problems. We report a 63-year-old female who experienced complete resolution of recurrent acute PVT in liver cirrhosis after treatment with rivaroxaban.
Administration, Oral ; Factor Xa Inhibitors/*therapeutic use ; Female ; Humans ; Liver Cirrhosis/*complications/diagnosis ; Middle Aged ; Portal Vein ; Recurrence ; Rivaroxaban/*therapeutic use ; Tomography, X-Ray Computed ; Venous Thrombosis/complications/diagnostic imaging/*drug therapy

Objective: To evaluate different methods' efficacy of controlling acute bleeding and managing long-term menstruation in patients with heavy menstrual bleeding (HMB) associated with antithrombotic therapy. Methods: The clinical data of 22 cases with HMB associated with antithrombotic therapy admitted to Peking University People's Hospital from January 2010 to August 2022 were analyzed, aged 39 years old (26-46 years). Changes in menstrual volume, hemoglobin (Hb), and quality of life were collected after control of acute bleeding and long-term menstrual management. Menstrual volume was assessed by pictorial blood assessment chart (PBAC), and quality of life was assessed by menorrhagia multi-attribute scale (MMAS). Results: (1) Treatment of acute bleeding: of the 22 cases with HMB associated with antithrombotic therapy, 16 cases were treated in our hospital and 6 in other hospital for emergency bleeding; of the 16 cases treated in our hospital, 3 underwent emergency intrauterine Foley catheter balloon compression due to severe bleeding (Hb decreased by 20 to 40 g/L within 12 hours). Of the 22 cases with antithrombotic therapy-related HMB, 15 (including 2 cases with severe bleeding) underwent emergency aspiration or endometrial resection, and intraoperative placement of levonorgestrel-releasing intrauterine system (LNG-IUS) followed by a significant reduction in bleeding volume; 3 cases had controlled acute bleeding after rivaroxaban dose reduction and continued observation; 2 cases were given gonadotropin-releasing hormone agonists to control acute bleeding in other hospital, of which 1 case was temporarily treated with periodic blood transfusion, and the other one patient underwent total hysterectomy; and 2 cases had temporary amenorrhea with oral mifepristone after intrauterine balloon compression or oral norethindrone. (2) Long-term menstrual management: of the 22 cases with antithrombotic therapy-related HMB, 15 had LNG-IUS placement and 12 had LNG-IUS placement for 6 months, and menstrual volume was significantly reduced [PBAC scores were 365.0 (272.5-460.0) vs 25.0 (12.5-37.5), respectively; Z=4.593, P<0.001], Hb was significantly increased [91.5 g/L (71.8-108.2 g/L) vs 128.5 g/L (121.2-142.5 g/L); Z=4.695, P<0.001], and quality of life was significantly improved [MMAS scores were 415.0 (327.5-472.5) vs 580.0 (570.0-580.0), respectively; Z=-3.062, P=0.002] before placement compared with 6 months after placement. Three rivaroxaban dose reduction patients' PBAC scores decreased by 20 to 35 but remained >100, and perceived quality of life did not change significantly. Two cases with temporary amenorrhea treated with oral mifepristone felt significantly improved quality of life, and the MMAS scores increased by 220 and 180, respectively. Conclusion: Intrauterine Foley catheter balloon compression, aspiration or endometrial ablation could be used to control acute bleeding in patients with antithrombotic therapy-related HMB, and LNG-IUS for long-term management could reduce menstrual volume, increase hemoglobin, and improve the quality of life of patients.
Female ; Humans ; Adult ; Menorrhagia/etiology* ; Fibrinolytic Agents/adverse effects* ; Levonorgestrel/adverse effects* ; Amenorrhea/drug therapy* ; Mifepristone/therapeutic use* ; Quality of Life ; Rivaroxaban/therapeutic use* ; Hemoglobins ; Intrauterine Devices, Medicated/adverse effects* ; Contraceptive Agents, Female