Antithrombotic Usage, Including Three-Year Outcomes With Dabigatran and Vitamin K Antagonists for Atrial Fibrillation, in Eastern Europe: A Descriptive Analysis From Phase 3 of the GLORIA-AF Registry.

BACKGROUND: Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation (GLORIA-AF) is a prospective registry of outcomes from patients with newly diagnosed AF at risk of stroke. In the propensity score (PS)-matched global population of phase 3 GLORIA-AF, at 3 years, dabigatran-treated patients experienced reduced risk for major bleeding, and similar risk for stroke and myocardial infarction, compared with vitamin K antagonist (VKA)-treated patients. STUDY QUESTION: Do patients in Eastern Europe benefit from treatment with dabigatran versus VKA? STUDY DESIGN: Descriptive analysis, without PS matching. To contextualize the Eastern Europe results of GLORIA-AF phase 3, we also descriptively analyzed the global population without PS matching. Consecutive patients with newly diagnosed AF and CHA2DS2-VASc-score ≥1 were enrolled until December 2016 in 38 countries (9 in Eastern Europe). MEASURES AND OUTCOMES: Three-year outcomes with dabigatran and VKA. RESULTS: In Eastern Europe, 1341 patients were eligible (6% of patients globally), and incidence rates (per 100 patient-years) for the following outcomes were numerically lower with dabigatran (N = 498) versus VKA (N = 466): major bleeding (0.26 vs. 0.90), all-cause death (2.04 vs. 3.50), and a composite of stroke, systemic embolism, myocardial infarction, life-threatening bleeding, and vascular death (1.37 vs. 1.92); stroke was comparable (0.51 vs. 0.50). All incidence rates were numerically lower in Eastern Europe versus the global population for both treatments. Chronic concomitant use of high bleeding risk medications (eg, nonsteroidal anti-inflammatories) was lower in Eastern Europe (dabigatran 3.8%, VKA 9.3%) than globally (dabigatran 14.8%, VKA 20.6%) and persistence with dabigatran was higher in Eastern Europe (76%) than globally (64%). CONCLUSIONS: Dabigatran was associated with numerically reduced major bleeding, all-cause death, and cardiovascular (CV) composite, with comparable risk of stroke versus VKA, in Eastern Europe. Limitations of this descriptive analysis include few CV events (n = 11 for stroke, in the dabigatran and VKA groups combined) and a lack of statistical analysis and PS matching, which precludes definitive conclusions; however, the CV outcomes in Eastern Europe were consistent with the beneficial impact of dabigatran versus VKA in the statistically analyzed global population with PS matching.

Reversal agents for current and forthcoming direct oral anticoagulants.

Over the past 20 years, there has been a shift from vitamin K antagonists to direct oral anticoagulants (DOACs), which include the thrombin inhibitor dabigatran and the factor Xa inhibitors apixaban, edoxaban, and rivaroxaban. Although DOACs are associated with less serious bleeding than vitamin K antagonists, bleeding still occurs with DOACs, particularly in the elderly and in those with comorbidities. Reversal of the anticoagulant effects of the DOACs may be needed in patients with serious bleeding and in those requiring urgent surgery or intervention. Reversal can be effected with specific agents, such as idarucizumab for dabigatran and andexanet alfa for apixaban, edoxaban, and rivaroxaban, or with non-specific agents, such as prothrombin complex concentrates, activated prothrombin complex concentrate, and recombinant activated factor VII. This paper (i) provides an update on when and how to reverse the DOACs, (ii) describes new reversal agents under development, and (iii) provides a strategic framework for the reversal of the factor XI inhibitors currently under investigation in phase three clinical trials.

Direct oral anticoagulants in trauma patients.

PURPOSE OF REVIEW: Direct oral anticoagulants (DOACs) are increasingly prescribed for prevention of thromboembolic events. Thus, trauma care providers are facing a steadily raising number of injured patients on DOACs. RECENT FINDINGS: Despite a predictable pharmacokinetic profile, the resulting plasma levels of trauma patients upon admission and bleeding risks remain uncertain. Therefore, recent guidelines recommend the measurement of DOAC plasma concentrations in injured patients. Alternatively, DOAC specific visco-elastic tests assays can be applied to identify DOAC patients at bleeding risk.Bleeding complications in trauma patients on DOACs are generally higher compared to nonanticoagulated subjects, but comparable to vitamin K antagonists (VKAs). In particular, a traumatic brain injury does not carry an increased risk of intracranial bleeding due to a DOAK intake compared to VKAs. Current studies demonstrated that up to 14% of patients with a hip fracture are on DOACs prior to surgery. However, the majority can be operated safely within a 24h time window without an increased bleeding rate.Specific antagonists facilitate rapid reversal of patients on DOACs. Idarucizumab for dabigatran, and andexanet alfa for apixaban and rivaroxaban have been approved for life threatening bleeding. Alternatively, prothrombin complex concentrate can be used. Dialysis is a potential treatment option for dabigatran and haemoabsorption with special filters can be applied in patients on FXa-inhibitors. SUMMARY: Current guidelines recommend the measurement of DOAC plasma levels in trauma patients. Compared to VKAs, DOACs do not carry a higher bleeding risk. DOAC specific antagonists facilitate the individual bleeding management.

Identifying treatment heterogeneity in atrial fibrillation using a novel causal machine learning method.

BACKGROUND: Lifelong oral anticoagulation is recommended in patients with atrial fibrillation (AF) to prevent stroke. Over the last decade, multiple new oral anticoagulants (OACs) have expanded the number of treatment options for these patients. While population-level effectiveness of OACs has been compared, it is unclear if there is variability in benefit and risk across patient subgroups. METHODS: We analyzed claims and medical data for 34,569 patients who initiated a nonvitamin K antagonist oral anticoagulant (non-vitamin K antagonist oral anticoagulant (NOAC); apixaban, dabigatran, and rivaroxaban) or warfarin for nonvalvular AF between 08/01/2010 and 11/29/2017 from the OptumLabs Data Warehouse. A machine learning (ML) method was applied to match different OAC groups on several baseline variables including, age, sex, race, renal function, and CHA2DS2 -VASC score. A causal ML method was then used to discover patient subgroups characterizing the head-to-head treatment effects of the OACs on a primary composite outcome of ischemic stroke, intracranial hemorrhage, and all-cause mortality. RESULTS: The mean age, number of females and white race in the entire cohort of 34,569 patients were 71.2 (SD, 10.7) years, 14,916 (43.1%), and 25,051 (72.5%) respectively. During a mean follow-up of 8.3 (SD, 9.0) months, 2,110 (6.1%) of patients experienced the composite outcome, of whom 1,675 (4.8%) died. The causal ML method identified 5 subgroups with variables favoring apixaban over dabigatran; 2 subgroups favoring apixaban over rivaroxaban; 1 subgroup favoring dabigatran over rivaroxaban; and 1 subgroup favoring rivaroxaban over dabigatran in terms of risk reduction of the primary endpoint. No subgroup favored warfarin and most dabigatran vs warfarin users favored neither drug. The variables that most influenced favoring one subgroup over another included Age, history of ischemic stroke, thromboembolism, estimated glomerular filtration rate, Race, and myocardial infarction. CONCLUSIONS: Among patients with AF treated with a NOAC or warfarin, a causal ML method identified patient subgroups with differences in outcomes associated with OAC use. The findings suggest that the effects of OACs are heterogeneous across subgroups of AF patients, which could help personalize the choice of OAC. Future prospective studies are needed to better understand the clinical impact of the subgroups with respect to OAC selection.

Clinical comprehensive evaluation of direct oral anticoagulants for patients with atrial fibrillation in China.

BACKGROUND: Direct oral anticoagulants (DOACs) are increasingly recommended over warfarin in stroke prevention for patients with non-valvular atrial fibrillation (AF). However, there is an important evidence gap in choosing the most appropriate DOAC for Chinese patients in clinical practice. METHODS: A multi-criteria decision analysis (MCDA) was adopted to build a scoring framework. Attributes and criteria were identified and determined by a scoping literature review, two rounds of Delphi surveys, and a consensus meeting. Weights of each attribute and criterion in the framework were determined using analytic hierarchy process (AHP). Evidence was collected based on the domestic or at least Asian data. Scoring methods for each criterion were developed depended on their characteristics and determined with an expert consensus meeting. Comprehensive scores of each DOAC were calculated based on the utility scores of each criterion and their corresponding weights. RESULTS: A total of 5 attributes, including safety, efficacy, costs/cost-effectiveness, suitability, and accessibility, were determined, and 16 criteria were under the 5 attributes. The safety and efficacy were ranked as the top two important attributes with the weights of 38.8% and 35.9%, respectively, while the suitability received the lowest weight of 7.9%. The comprehensive score for edoxaban was the highest (72.3), followed by dabigatran (49.7), rivaroxaban (37.9), and apixaban (35.8). CONCLUSIONS: This study provided a scoring framework developed for comprehensive evaluation of DOACs in China. The ranking of DOACs could help to support the decision-making in clinical practice. The framework could provide a reference for comprehensive evaluation of other drugs.

Oral direct thrombin inhibitors or oral factor Xa inhibitors versus conventional anticoagulants for the treatment of deep vein thrombosis.

BACKGROUND: Deep vein thrombosis (DVT) is a condition in which a clot forms in the deep veins, most commonly of the leg. It occurs in approximately one in 1000 people. If left untreated, the clot can travel up to the lungs and cause a potentially life-threatening pulmonary embolism (PE). Previously, a DVT was treated with the anticoagulants heparin and vitamin K antagonists. However, two forms of direct oral anticoagulants (DOACs) have been developed: oral direct thrombin inhibitors (DTIs) and oral factor Xa inhibitors, which have characteristics that may be favourable compared to conventional treatment, including oral administration, a predictable effect, lack of frequent monitoring or dose adjustment and few known drug interactions. DOACs are now commonly being used for treating DVT: recent guidelines recommended DOACs over conventional anticoagulants for both DVT and PE treatment. This Cochrane Review was first published in 2015. It was the first systematic review to measure the effectiveness and safety of these drugs in the treatment of DVT. This is an update of the 2015 review.  OBJECTIVES: To assess the effectiveness and safety of oral DTIs and oral factor Xa inhibitors versus conventional anticoagulants for the long-term treatment of DVT. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 1 March 2022. SELECTION CRITERIA: We included randomised controlled trials (RCTs) in which people with a DVT, confirmed by standard imaging techniques, were allocated to receive an oral DTI or an oral factor Xa inhibitor compared with conventional anticoagulation or compared with each other for the treatment of DVT.  DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were recurrent venous thromboembolism (VTE), recurrent DVT and PE. Secondary outcomes included all-cause mortality, major bleeding, post-thrombotic syndrome (PTS) and quality of life (QoL). We used GRADE to assess the certainty of evidence for each outcome. MAIN RESULTS: We identified 10 new studies with 2950 participants for this update. In total, we included 21 RCTs involving 30,895 participants. Three studies investigated oral DTIs (two dabigatran and one ximelagatran), 17 investigated oral factor Xa inhibitors (eight rivaroxaban, five apixaban and four edoxaban) and one three-arm trial investigated both a DTI (dabigatran) and factor Xa inhibitor (rivaroxaban). Overall, the studies were of good methodological quality. Meta-analysis comparing DTIs to conventional anticoagulation showed no clear difference in the rate of recurrent VTE (odds ratio (OR) 1.17, 95% confidence interval (CI) 0.83 to 1.65; 3 studies, 5994 participants; moderate-certainty evidence), recurrent DVT (OR 1.11, 95% CI 0.74 to 1.66; 3 studies, 5994 participants; moderate-certainty evidence), fatal PE (OR 1.32, 95% CI 0.29 to 6.02; 3 studies, 5994 participants; moderate-certainty evidence), non-fatal PE (OR 1.29, 95% CI 0.64 to 2.59; 3 studies, 5994 participants; moderate-certainty evidence) or all-cause mortality (OR 0.66, 95% CI 0.41 to 1.08; 1 study, 2489 participants; moderate-certainty evidence). DTIs reduced the rate of major bleeding (OR 0.58, 95% CI 0.38 to 0.89; 3 studies, 5994 participants; high-certainty evidence).   For oral factor Xa inhibitors compared with conventional anticoagulation, meta-analysis demonstrated no clear difference in recurrent VTE (OR 0.85, 95% CI 0.71 to 1.01; 13 studies, 17,505 participants; moderate-certainty evidence), recurrent DVT (OR 0.70, 95% CI 0.49 to 1.01; 9 studies, 16,439 participants; moderate-certainty evidence), fatal PE (OR 1.18, 95% CI 0.69 to 2.02; 6 studies, 15,082 participants; moderate-certainty evidence), non-fatal PE (OR 0.93, 95% CI 0.68 to 1.27; 7 studies, 15,166 participants; moderate-certainty evidence) or all-cause mortality (OR 0.87, 95% CI 0.67 to 1.14; 9 studies, 10,770 participants; moderate-certainty evidence). Meta-analysis showed a reduced rate of major bleeding with oral factor Xa inhibitors compared with conventional anticoagulation (OR 0.63, 95% CI 0.45 to 0.89; 17 studies, 18,066 participants; high-certainty evidence).  AUTHORS' CONCLUSIONS: The current review suggests that DOACs may be superior to conventional therapy in terms of safety (major bleeding), and are probably equivalent in terms of efficacy. There is probably little or no difference between DOACs and conventional anticoagulation in the prevention of recurrent VTE, recurrent DVT, pulmonary embolism and all-cause mortality. DOACs reduced the rate of major bleeding compared to conventional anticoagulation. The certainty of evidence was moderate or high.

When and How to Use Reversal Agents for Direct Oral Anticoagulants?

PURPOSE OF REVIEW: Our objective is to describe currently available reversal agents for direct oral anticoagulants (DOACs), their target population, the available clinical practice recommendations and future directions. RECENT FINDINGS: Specific (idarucizumab for dabigatran and andexanet alfa for direct factor Xa inhibitors) and non-specific (prothrombin complex concentrates) reversal agents are effective in neutralizing the anticoagulant effect of DOACs. New investigational antidotes such as ciraparantag and VMX-C001 offer an alternative to andexanet alfa in reversing the anticoagulant activity of direct oral factor Xa inhibitors, but more clinical data are needed before they could be licensed for use. Specific reversal agents are recommended for use in clinical situations within their licensed indications (i.e.: reversal of DOACs in patients with severe uncontrolled or life-threatening bleeding or in need of emergency surgery or other invasive procedures), while non-specific reversal agents may be used when specific antidotes are not available or indicated.

Reversing dabigatran effect with idarucizumab to enable intravenous thrombolysis in patients with acute ischaemic stroke - a single centre experience.

INTRODUCTION: Our study analysed the safety and effectiveness of idarucizumab in enabling intravenous thrombolysis (IVT) in dabigatran-treated patients with acute ischaemic stroke (AIS). CLINICAL RATIONALE FOR THE STUDY: New oral anticoagulants (NOAC), including dabigatran, are the first-choice treatment option for preventing ischaemic stroke in patients with non-valvular atrial fibrillation (AF). However, a significant percentage of AF patients develops AIS despite NOAC treatment. According to current guidelines, treatment with IVT is contraindicated in patients who have received NOAC within the last 48 hours. Idarucizumab is a fragment of a monoclonal antibody that reverses the anticoagulation effect of dabigatran. The latest research shows that it can enable safe and successful IVT in patients with recent dabigatran intake, but more data is needed to confirm the safety and effectiveness of such treatment. MATERIAL AND METHODS: Our study included dabigatran-treated patients who received idarucizumab to allow AIS treatment with IVT in the University Hospital in Kraków (Poland) from December 2018 to June 2023. We gathered data on their past medical history, stroke severity, course of treatment and outcomes as defined by modified Rankin Scale (mRS) and National Institutes of Health Stroke Scale (NIHSS) scores at discharge. A good functional outcome was defined as mRS 0-2 points at discharge. RESULTS: This observational study included 19 patients (13 male and six female) with a median age of 74 (IQR = 13) years. In all patients (100%), the reason for dabigatran treatment was AF. A good functional outcome after treatment (mRS 0-2) was achieved in 68.4% of patients, but mRS was already ≥ 3 points before stroke onset in three (15.8%) patients. Haemorrhagic transformation of stroke occurred in three (15.8%) patients, including symptomatic intracranial haemorrhage in two (10.5%). The mortality rate was 5.3%. CONCLUSIONS AND CLINICAL IMPLICATIONS: Our study results are in line with previous research on this topic, showing that IVT after idarucizumab can be successfully administered and is reasonably safe in dabigatran-treated patients with AIS.

Choice of oral anticoagulant prescribed by general practices in Wales: Application of Dirichlet regression and linked data.

AIMS: There has been sustained growth in the prescribing of direct oral anticoagulants (OACs) in primary care in the UK. Given the different indications, properties and prices of OACs, variation between prescribers is expected; however, a high level of variation may be evidence of inappropriate or suboptimal prescribing. This study examined the variation in the relative use of OACs in primary care in Wales. METHODS: Data on total defined daily doses of all community-dispensed OACs in 2019 were linked at the GP practice level with disease registers, patient demographic data and GP and patient numbers. The relative use of each OAC, as a fraction of all OACs prescribed, was analysed using Dirichlet regression to quantify the association between prescribing patterns and practice and area-level characteristics. RESULTS: Across 417 GP practices, the mean (range) in the relative prescribing of warfarin was 37% (6%-64%), apixaban was 32% (2%-65%), rivaroxaban 23% (0%-66%), dabigatran 3% (0%-23%) and edoxaban 6% (0%-59%). Statistical modelling provided strong evidence that prescribing patterns are associated with a GP practice's health board and also their nearest major hospital. Compared to the null model, a model including health board resulted in a 15% fall in Akaike information criterion, increasing to 20% with the addition of nearest major hospital and 27% including further covariates. CONCLUSION: Systematic variation in OAC prescribing, by health board and based on nearest hospital, indicates that factors other than patient clinical characteristics and preferences may be influencing prescribing decisions.

Effectiveness and safety of intracranial events associated with the use of direct oral anticoagulants for atrial fibrillation: A systematic review and meta-analysis of 92 studies.

AIMS: Observational studies have investigated the effectiveness and safety of direct oral anticoagulants (DOACs) and vitamin K antagonists (VKAs) used in nonvalvular atrial fibrillation. We performed a systematic review and meta-analysis assessing the risk of ischaemic stroke, thromboembolism (TE) and intracranial haemorrhage (ICH) associated with the use of DOACs and VKAs. METHODS: Medline and Embase were systematically searched until April 2021. Observational studies were gathered and hazard ratios (HRs) with 95% confidence intervals (CI) were extracted. Subgroup analyses based on DOAC doses, history of chronic kidney disease, stroke, exposure to VKA, age and sex were performed. A random-effects model was used. RESULTS: We included 92 studies and performed 107 comparisons. Apixaban was associated with lower risk of stroke (HR: 0.82, 95% CI: 0.68-0.99) compared to dabigatran. Rivaroxaban was associated with lower risk of stroke (HR: 0.90, 95% CI: 0.83-0.98) compared to VKA. Dabigatran (HR: 0.85, 95% CI: 0.80-0.91), rivaroxaban (HR: 0.83, 95% CI: 0.77-0.89) and apixaban (HR: 0.75, 95% CI: 0.65-0.86) were associated with lower risk for TE/stroke compared to VKA. Apixaban (HR: 1.32, 95% CI: 1.03-1.68) and rivaroxaban (HR: 1.58, 95% CI: 1.31-1.89) were associated with higher risk of ICH compared to dabigatran. Dabigatran (HR: 0.48, 95% CI: 0.44-0.52), apixaban (HR: 0.60, 95% CI: 0.49-0.73) and rivaroxaban (HR: 0.73, 95% CI: 0.65-0.81) were associated with lower risk of ICH compared to VKA. CONCLUSION: Our study demonstrated significant differences in the risk of ischaemic stroke, TE/stroke and ICH associated with individual DOACs compared to both other DOACs and VKA.

Non-vitamin K antagonist oral anticoagulants in venous thromboembolism patients: a meta-analysis of real-world studies.

BACKGROUND: The real-world studies on recurrent venous thromboembolism (VTE) and bleeding events of non-vitamin K antagonist oral anticoagulants (NOACs) in VTE patients have reported conflicting findings. Our study aimed to provide the direct comparison evidence of different NOACs for VTE patients in clinical practice settings. METHODS: Search of the medical literature was conducted using PubMed, Web of Science, EMBASE, Clinical Trials.gov, and the Cochrane Library from inception to March 22, 2021. Among the 19,996 citations retrieved, a total of 63,144 patients from 6 studies were analyzed. Clinical outcomes included recurrent VTE, death, and different bleeding events. RESULTS: Adjusted hazard ratio (HR) analysis suggested that apixaban had significant lower bleeding riskthan rivaroxaban (major, minor and any bleeding: HR = 0.61, 0.56, 0.70; p = 0.008, < 0.0001, 0.006, respectively), but no statistics difference found in recurrent VTE events (HR = 1.02, 95% confidence interval (CI) 0.71-1.47, p = 0.93). There was no significant difference of major bleeding between dabigatran and rivaroxaban (odds ratios (OR) = 0.41, 95% CI 0.09-1.90, p = 0.25), apixaban and dabigatran (OR 0.64, 95% CI 0.15-2.72, p = 0.83). No significant difference was found in the comparison of edoxaban and other NOACs in VTE recurrence, major bleeding and composite outcome. CONCLUSIONS: In the prevention of bleeding events, apixaban was associated with a lower risk than rivaroxaban, but equivalent efficacy for different NOACs in prevention of recurrent VTE. Evidence generated from the meta-analysis based on real-world data can help to guide selection between apixaban and rivaroxaban in routine clinical practice. TRIAL REGISTRATION: This systematic review and meta-analysis were conducted and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis and Meta-analysis of Observational Studies in Epidemiology statements and was registered with PROSPERO (CRD42019140553).

Cost-effectiveness of anticoagulants for preventing stroke in patients with non-valvular atrial fibrillation in mainland China.

WHAT IS KNOWN AND OBJECTIVE: With the high cost, the long-term persistence of new oral anticoagulants (NOACs) was lower than that of warfarin in Chinese patients with non-valvular atrial fibrillation (NVAF) for a long time. The prices of NOACs (apixaban, rivaroxaban and dabigatran) decreased significantly over the past year in mainland China. The objective of this study was to evaluate the cost-effectiveness of NOACs versus warfarin for preventing stroke in patients with NVAF from a Chinese healthcare system perspective. METHODS: A decision tree and Markov model were used to assess the treatment strategies of four NOACs versus warfarin over a lifetime horizon. For each treatment strategy, the total lifetime cost, quality-adjusted life-years (QALY) and incremental cost-effectiveness ratio (ICER) were calculated. The impact of parameter uncertainties on base-case analysis results was evaluated using sensitivity analyses. RESULTS AND DISCUSSION: In the base-case analysis, compared with warfarin, apixaban had a decreased total lifetime cost of USD 389 and rivaroxaban of USD 1482, while low-dose dabigatran had an increased total lifetime cost of USD 925 and high-dose dabigatran of USD 6641, with QALY increasing by 0.53, 1.32, 0.92 and 1.83, respectively. The ICER of low-dose dabigatran versus warfarin was USD 1005 per QALY gain, while those of apixaban (-USD 734 per QALY gain) and rivaroxaban (-USD 1123 per QALY gain) were negative. One-way and probabilistic sensitivity analyses indicated that the base-case results were robust by applying certain varying parameters to the model. WHAT IS NEW AND CONCLUSION: These four NOAC (apixaban, rivaroxaban, low-dose dabigatran and high-dose dabigatran) treatment strategies were cost-effective compared with warfarin and recommended as substitutes for warfarin treatment for preventing stroke in patients with NVAF in the healthcare system of China, which might be driven by large drug price reductions in the past year.

Safety and efficacy of low-dose non-vitamin K antagonist oral anticoagulants versus warfarin after left atrial appendage closure with the Watchman device.

BACKGROUND/PURPOSE: Anticoagulant therapy is suggested within 45 days after Watchman device implantation for stroke prevention in patients with atrial fibrillation (AF). A previous study demonstrated that non-vitamin K antagonist oral anticoagulants (NOACs) were a feasible peri- and postprocedural alternative to warfarin. The present study aimed to compare the safety and efficacy of using different anticoagulants (low-dose NOACs vs. warfarin) within 45 days after Watchman device implantation in a Chinese population. METHODS: Patients with successful Watchman device implantation from October 2014 to June 2020 were included. All patients received anticoagulants within 45 days after the procedure, and those patients were divided into three groups according to the type of postprocedural anticoagulants. Transesophageal echocardiography follow-up was performed 45 days post procedure to assess residual flow and the occurrence of device-related thrombus (DRT). RESULTS: A total of 368 patients were enrolled in the study. The study population was divided into three groups: the warfarin group (n = 77), the dabigatran group (n = 165) and the rivaroxaban group (n = 126). Periprocedural major bleeding was higher in the warfarin group (2.6% vs. 0% vs. 0%, P = 0.043), while minor bleeding was comparable among the groups (3.9% vs. 1.2% vs. 0.8%, P = 0.230). No periprocedural transient ischemic attack/stroke occurred. At follow-up, the incidence of DRT was higher in the warfarin group than in the other groups (4.2% vs. 0.6% vs. 0.8%; P = 0.116), but the difference was not statistically significant. The rates of thromboembolic and bleeding events were similar in the three groups. CONCLUSION: The safety and efficacy of low-dose dabigatran and rivaroxaban were comparable to those of warfarin within 45 days after Watchman device implantation in a Chinese population.

Oral Anticoagulant Use in Patients With Atrial Fibrillation and Chronic Kidney Disease: A Review of the Evidence With Recommendations for Australian Clinical Practice.

Chronic kidney disease is common in patients with atrial fibrillation (AF) and is associated with heightened risks of stroke/systemic embolisation and bleeding. In this review we outline the evidence for AF stroke prevention in kidney disease, identify current knowledge gaps, and give recommendations for anticoagulation at various stages of chronic kidney disease. Overall, anticoagulation is underused. Warfarin use becomes increasingly difficult with advancing kidney disease, with difficulty maintaining international normalised ratio (INR) in therapeutic range, increased risk of intracranial and fatal bleeding compared to non-vitamin K oral anticoagulants (NOACs), and high rates of discontinuation. Similarly, the direct thrombin inhibitor dabigatran is not recommended as it is predominantly renally excreted with consequent increased plasma levels and bleeding risk with advanced kidney disease. The Factor Xa inhibitors apixaban and rivaroxaban have less renal excretion (25-35%), modest increases in plasma levels with advancing kidney disease, and are the preferred first line choice for anticoagulation in moderate kidney disease based on strong evidence from randomised clinical trials (RCTs). In severe kidney disease there is a paucity of RCT data, but extrapolation of the pharmacokinetic and RCT data for moderate kidney disease, and observational studies, support the considered use of dose-adjusted Factor Xa inhibitors unless the bleeding risk is prohibitive. In Australia, apixaban is approved for creatinine clearance down to 25 mL/min, and rivaroxaban down to 15 mL/min. For end-stage kidney disease warfarin is the only agent approved, but we recommend against anticoagulation (except in selected cases) due to high bleeding risk, multiple co-morbidities, and questionable benefit.

[Mitral Mechanical Valve Thrombosis after Switching to Dabigatran].

The patient is a 76-year-old man who underwent aortic and mitral valve replacement 30 years ago, both with mechanical valves. He had been on anticoagulant therapy with warfarin, which was switched to dabigatran two years ago by his primary care physician. He developed shortness of breath afterward and was taken to the hospital with heart failure. Fluoroscopy of the valve revealed that one leaflet of the prosthetic mitral valve was immobile. The patient was diagnosed with a thrombosed valve and underwent an urgency repeat mitral valve replacement. He recovered uneventfully and was discharged without complication. During long years, some patients may have comorbidities and get frail. Medical principle may change, and various treatment methods with more and more complex indications may emerge. But in patients with mechanical heart valves, warfarin still remains the only choice for anticoagulation therapy.

Assessment of exposure to direct oral anticoagulants in elderly hospitalised patients.

It is unclear whether elderly patients established on direct oral anticoagulants (DOACs) have greater exposure to these drugs, which could subsequently increase their risk of bleeding. We assessed DOAC exposure and factors affecting it in a real-world elderly cohort of patients. For this, 151 medically stable hospital inpatients (76 established on apixaban, 61 on rivaroxaban, 14 on dabigatran) with a median [interquartile range (IQR)] age of 84 (78-89) years were recruited. Patients provided blood samples for measurement of peak and trough plasma DOAC concentrations. There was up to 48-fold and 13-fold variation in trough and peak plasma drug concentrations respectively. A significantly greater proportion of patients on apixaban had peak plasma drug concentrations within the reported ranges compared to those on either rivaroxaban or dabigatran (82·9% vs. 44·3% vs. 64·3% respectively; P < 0·001). A third of the variability in DOAC plasma concentrations was attributed to the influences of DOAC dosage, renal function and gender. To what extent the observed increases in DOAC exposure in the older patients is the cause of their increased risk of bleeding, which could potentially be ameliorated by dosing titration, requires further investigation.

Direct oral anticoagulants: evidence and unresolved issues.

Currently licenced direct oral anticoagulants selectively target thrombin (eg, dabigatran) or coagulation factor Xa (eg, apixaban, betrixaban, edoxaban, and rivaroxaban). Designed to be given in fixed doses without routine monitoring, direct oral anticoagulants have a lower propensity for food and drug interactions than do vitamin K antagonists, and in randomised controlled trials involving around 250 000 patients, they were at least as effective for prevention and treatment of thrombosis and were associated with a lower risk of life-threatening bleeding. The absolute benefits of direct oral anticoagulants over vitamin K antagonists are modest; however, guidelines recommend them in preference to vitamin K antagonists for most indications because of their ease of use and superior safety. The greatest benefits of direct oral anticoagulants are likely to be in patients who were previously deemed unsuitable for vitamin K antagonist therapy. The emergence of generic preparations is expected to further increase the uptake of direct oral anticoagulants, particularly in countries where they are currently not widely used because of cost. Direct oral anticoagulants are contraindicated in patients with mechanical heart valves and should be used with caution or avoided in patients with advanced kidney or liver disease. In this Therapeutics paper, we review the pharmacology of direct oral anticoagulants, summarise the evidence that led to their approval and incorporation into treatment guidelines, and explore key unresolved issues. We also briefly discuss future perspectives for the development of oral anticoagulants.

Persistence and adherence to non-vitamin K antagonist oral anticoagulant treatment in patients with atrial fibrillation across five Western European countries.

AIMS: To assess persistence and adherence to non-vitamin K antagonist oral anticoagulant (NOAC) treatment in patients with atrial fibrillation (AF) in five Western European healthcare settings. METHODS AND RESULTS: We conducted a multi-country observational cohort study, including 559 445 AF patients initiating NOAC therapy from Stockholm (Sweden), Denmark, Scotland, Norway, and Germany between 2011 and 2018. Patients were followed from their first prescription until they switched to a vitamin K antagonist, emigrated, died, or the end of follow-up. We measured persistence and adherence over time and defined adequate adherence as medication possession rate ≥90% among persistent patients only. RESULTS: Overall, persistence declined to 82% after 1 year and to 63% after 5 years. When including restarters of NOAC treatment, 85% of the patients were treated with NOACs after 5 years. The proportion of patients with adequate adherence remained above 80% throughout follow-up. Persistence and adherence were similar between countries and was higher in patients starting treatment in later years. Both first year persistence and adherence were lower with dabigatran (persistence: 77%, adherence: 65%) compared with apixaban (86% and 75%) and rivaroxaban (83% and 75%) and were statistically lower after adjusting for patient characteristics. Adherence and persistence with dabigatran remained lower throughout follow-up. CONCLUSION: Persistence and adherence were high among NOAC users in five Western European healthcare settings and increased in later years. Dabigatran use was associated with slightly lower persistence and adherence compared with apixaban and rivaroxaban.

Adherence to direct oral anticoagulant treatment for atrial fibrillation in the Netherlands: A surveillance study.

BACKGROUND: Adherence to direct oral anticoagulants (DOACs) in patients with atrial fibrillation in every day practice may be less than in clinical trials. AIMS: To assess adherence to DOACs in atrial fibrillation patients in every day practice and identify predictors for non-adherence. METHODS: Individual linked dispensing data of atrial fibrillation patients who used DOACs were obtained from the Foundation for Pharmaceutical Statistics covering the Netherlands between 2012 and 2016. One year adherence to DOAC was calculated for initial DOAC as proportion of days covered (PDC) ≥80% and the association between clinical variables and adherence was assessed using logistic regression. In addition, we measured non-persistence, that is, patients who completely stopped their initial DOAC within 1 year follow-up. RESULTS: A total of 4797 apixaban-, 20 454 rivaroxaban- and 18 477 dabigatran users were included. The mean age was 69 years (n = 43 910), which was similar for the DOAC types. The overall proportion of patients with PDC ≥80% was 76%, which was highest for apixaban- (87%), followed by dabigatran- (80%) and rivaroxaban (69%) users. Multivariable analyses revealed that age ≤60 years, no concomitant drug use were predictors for non-adherence. Of atrial fibrillation patients who continued treatment, 97% had a PDC ≥80%, compared with only 56% for those who discontinued their DOAC treatment within 1 year. CONCLUSIONS: Non-adherence to DOACs was associated with age ≤60 years and no concomitant drugs use. Non-adherence was higher in patients who later discontinued DOAC treatment. Results of our study support research into interventions to improve adherence.

Working smarter, not harder: evaluating a population health approach to anticoagulation therapy management.

Inappropriate direct acting oral anti-coagulants (DOAC) prescribing increases the risk of adverse events. Population health management tools (PMTs) could help reduce adverse events through the early, efficient identification of questionable prescribing practices, but the impact of such a tool remains unknown. We evaluated the effect of PMT use on questionable DOAC dosing rates within 40 VHA medical centers and whether this effect differed by DOAC indication or agent. Medical centers were divided into PMT user or standard of care (SOC) groups based upon high or low tool access in the prior year. Questionable DOAC dosing rate was defined as the proportion of patients prescribed DOACs who were also flagged by the tool. Chi-square tests were used to determine if PMT user versus SOC groups differed with high (above 15.3%) versus low (below 15.3%) questionable dosing rates. T-tests were used to determine if mean questionable dosing rates significantly differed between the PMT user and SOC groups. DOAC PMT users were classified less frequently as being 'High" questionable dosage rate compared to SOCs (25% PMT vs. 75% SOC, respectively, p = 0.002). DOAC PMT utilization within the overall cohort was associated with a 4.3% absolute reduction in questionable DOAC dosing rates (13.2% PMT vs 17.5% SOC; p = 0.01). Tool use within the atrial fibrillation (AF) subgroup was associated with a 5.1% absolute reduction in questionable dosing rates (10.4% SOC vs. 5.3% PMT, p < 0.001). Tool use was also associated with lower questionable dosing rates in the apixaban (p < 0.001), dabigatran (p = 0.03) and AF plus venous thromboembolism (p < 0.001) subgroups. In our study, PMT use was associated with reduced questionable DOAC dosing, a difference most pronounced within AF patients. A population health approach has the potential to reduce adverse events among patients prescribed DOACs.