Comparative risk of major bleeding with new oral anticoagulants (NOACs) and phenprocoumon in patients with atrial fibrillation: a post-marketing surveillance study

Comparative effectiveness of factor Xa non-vitamin K antagonist oral anticoagulants versus phenprocoumon in patients with non-valvular atrial fibrillation

BACKGROUND

Non-vitamin K antagonist oral anticoagulants (NOACs) have largely supplanted vitamin K antagonists (VKAs) for oral anticoagulation in non-valvular atrial fibrillation (NVAF). However, data on the real-world effectiveness of NOACs vs. phenprocoumon, a VKA widely used in Germany, are limited. The RELOADED study aimed to compare effectiveness of factor Xa NOACs and phenprocoumon in NVAF in clinical practice.

METHODS

Patients who started on a factor Xa NOAC or phenprocoumon for NVAF during the study period were enrolled from the Institute for Applied Healthcare Research Berlin. Patients were followed from first prescription until the end of exposure or available data. Primary outcomes were analyzed by Cox proportional hazard regression models and included ischemic stroke and systemic embolism for effectiveness, and intracranial hemorrhage (ICH) for safety. Subgroups of interest were patients with diabetes and patients with renal impairment.

RESULTS

The total study population was 64,920; 36.3% of patients initiated phenprocoumon, 34.4% initiated rivaroxaban, 25.0% apixaban, and 4.4% edoxaban. Treatment with phenprocoumon is associated with a similar risk of ischemic stroke/systemic embolism as treatment with rivaroxaban or apixaban; while rivaroxaban (adjusted hazard ratio [HR] 0.57, 95% confidence interval [CI] 0.43-0.75) and apixaban (adjusted HR 0.43, 95% CI 0.31-0.6) were associated with a lower risk of ICH compared to phenprocoumon in NVAF patients. The use of rivaroxaban and apixaban was associated with a lower risk of developing kidney failure in patients with diabetes or renal impairment in comparison to those treated with phenprocoumon.

CONCLUSION

The factor Xa NOACs rivaroxaban and apixaban demonstrated similar effectiveness and lower rates of ICH compared with phenprocoumon in this study.

Limitations in Contemporary Pharmacological Stroke Prevention Therapies in Atrial Fibrillation: A Descriptive Literature Review

The most common arrhythmia, atrial fibrillation (AF), increases with age and is associated with a 5-fold increased risk of stroke. Although lifelong oral anticoagulation (OAC) is strongly recommended for stroke prevention in patients with AF and CHA2DS2-VASc ≥ 2 only 50-60% of patients in Western countries belonging to this group are treated with oral anticoagulants, and less than half of these adhere to therapy over time. Before 2010, the numerous limitations associated with vitamin K antagonists (VKAs) were considered to be the reason behind OAC underuse; however, the approval of direct oral anticoagulants (DOACs) that require once- or twice-daily intake, no regular blood tests and fewer drug-food interactions has resulted in only modest improvements in OAC use and adherence.

Nonvitamin K oral anticoagulants with proton pump inhibitor cotherapy ameliorated the risk of upper gastrointestinal bleeding

Proton pump inhibitors (PPIs) can reduce the risk of upper gastrointestinal bleeding (UGIB) in patients who are taking oral anticoagulants. This study aimed to identify the association between NOACs with PPI cotherapy and UGIB. This retrospective cohort analysis included patients over the age of 18 years who were using NOACs between 2013 and 2020. NOAC categories, concomitant medications, endoscopic findings, the HAS-BLED score and the Charlson Comorbidity Index score were recorded. Using Poisson regression models, the relationship between UGIB events and risk factors was analyzed. Throughout a mean follow-up of 29.5 months, 14 (5.1%) individuals experienced UGIB. The incidence of UGIB was greater in patients receiving NOACs without PPIs (2.7 [1.26-5.60] per 1000) than in those receiving NOACs with PPIs (1.3 [0.61-2.67] per 1000). Patients receiving NOACs with PPIs had a 79.2% lower incidence of UGIB than patients receiving NOAC monotherapy (RR 0.208, 95% CI 0.061-0.706; p = 0.012). Female sex and the HAS-BLED score were associated with UGIB (RR 5.043; 95% CI 1.096-23.20; p = 0.038; RR 2.024; 95% CI 1.095-3.743; p = 0.024, respectively). Patients receiving NOAC and PPI cotherapy had a lower incidence of UGIB than those receiving NOACs alone, and female sex was a risk factor for UGIB in NOAC-treated patients.

Risk Profiles of New Users of Oral Anticoagulants Between 2011 and 2019 in Germany

Purpose

Over the last decade, the use of direct oral anticoagulants (DOACs) has strongly increased. We aimed to describe and compare risk profiles including potential changes over time among persons with non-valvular atrial fibrillation initiating treatment with different DOACs or phenprocoumon (vitamin K antagonist) between 2011 and 2019 in Germany.

Patients and Methods

Using the German Pharmacoepidemiological Research Database (GePaRD; claims data of ~20% of the German population), we identified persons with a first dispensing of phenprocoumon or a DOAC and a diagnosis of non-valvular atrial fibrillation between August 2011 and December 2019. We described the morbidity of included patients prior to treatment initiation, stratified by year of treatment initiation.

Results

Overall, we included 448,028 new users (phenprocoumon: N = 118,117, rivaroxaban: N = 130,997, apixaban: N = 130,300, edoxaban: N = 38,128, dabigatran: N = 30,486). Comparing new DOAC users in 2019, the proportion with prior ischemic stroke was highest for dabigatran (17%) and lowest for rivaroxaban (8%). The proportion with prior major bleeding was also highest for dabigatran (25%) and lowest for edoxaban (20%). New users of apixaban were oldest and, eg, showed the highest prevalence of congestive heart failure. Changes over time were most pronounced for phenprocoumon. For example, among persons initiating phenprocoumon in 2012 vs 2019, the proportion with prior major bleeding increased from 18% to 35%; the proportion with renal disease increased from 20% to 36% and the proportion with liver disease from 18% to 24%.

Conclusion

This study demonstrated differences in risk profiles between new users of different oral anticoagulants and substantial changes over time among new phenprocoumon users. These differences have to be considered in head-to-head comparisons of these drugs based on observational data, especially regarding potential unmeasured confounding.

Increased major bleeding incidence in atrial fibrillation patients with apixaban: a review of Japanese post-marketing surveillance studies of direct oral anticoagulants

Large-scaled post-marketing surveillance studies (PMSSs) of 4 direct oral anticoagulants (DOACs) for stroke prevention in non-valvular atrial fibrillation (AF) were conducted since 2011 in Japan, and the results of the last one have recently been published. Each reported a more than acceptable ischemic stroke prevention. The major bleeding rates were also acceptably low and comparable to each other in the PMSSs of dabigatran (J-dabigatran), rivaroxaban (XAPASS), and edoxaban (ETNA-AF-Japan). However, the incidence in PMSS of apixaban (STANDARD) was more than double the others. This finding appeared to contradict the globally accepted theory that apixaban is less likely than other DOACs to cause bleeding events. Possible responsible mechanisms included (1) the age and kidney function, (2) concomitant antiplatelet therapy, (3) drug actions, (4) follow-up duration, and (5) dose reduction criteria. Similarities in the clinical background shared by the 4 different PMSSs' participants and knowledge from previous studies did not support a dominant contribution of any of those former 4 factors to the increased major bleeding incidence in STANDARD. A possibility of the 5th factor was then examined. An estimated calculation we created showed that apixaban's dose reduction criteria was strict enough to considerably reduce the opportunity for participants to take its reduced rather than standard dose. We then successfully simulated how the "strict" dose reduction criteria would have increased the bleeding event rates under DOAC therapy. The discussion in this review may therefore raise a question about the validity of the current dose reduction criteria of apixaban for Japanese AF patients.

Pyrazole-Based Thrombin Inhibitors with a Serine-Trapping Mechanism of Action: Synthesis and Biological Activity

New antithrombotic drugs are needed to combat thrombosis, a dangerous pathology that causes myocardial infarction and ischemic stroke. In this respect, thrombin (FIIa) represents an important drug target. We herein report the synthesis and biological activity of a series of 1H-pyrazol-5-amine-based thrombin inhibitors with a serine-trapping mechanism of action. Among synthesized compounds, flexible acylated 1H-pyrazol-5-amines 24e, 34a, and 34b were identified as potent 16-80 nM thrombin inhibitors, which showed practically no off-targeting effect against other physiologically relevant serine proteases. To prove that synthesized compounds are covalent thrombin inhibitors, the most potent derivative 24e (FIIa IC₅₀ = 16 nM) was studied in a mass-shift assay, where it has been shown that 24e transfers its acyl moiety (pivaloyl) to the catalytic Ser195 of thrombin. Performed herein docking studies also confirmed the covalent mechanism of thrombin inhibition by synthesized compounds. Acylated aminopyrazoles found during this study showed only limited effects on plasma coagulation in activated partial thrombin time (aPTT) and prothrombin time (PT) in vitro assays. However, such thrombin inhibitors are expected to have virtually no effect on bleeding time and can be used as a starting point for developing a safer alternative to traditional non-covalent anticoagulants.

Moderne Antikoagulation mit FXa-Inhibitoren in der Onkologie: Ist die gastrointestinale Blutungsrate (mit)-entscheidend?

Das erhöhte Thrombose- und Blutungsrisiko bei aktiver Tumorerkrankung wird als sog. „thrombo-hämorrhagisches Syndrom“ bezeichnet, welches hohe Anforderungen an die Antikoagulation stellt. Aktuell liegen 4 randomisierte, prospektive Studien zum Einsatz von neuen, nicht Vitamin K-abhängigen oralen Antikoagulantien (NOAK) zur Behandlung von in der Onkologie aufgetretenen venösen Thromboembolien (VTE) vor. Dabei wurden die FXa-Inhibitoren Rivaroxaban, Edoxaban und zweimal Apixaban jeweils in einzelnen Studien gegenüber dem Standardtherapeutikum Dalteparin eingesetzt. Da es keinen direkten Head-to-Head-Vergleich der genannten FXa-Inhibitoren innerhalb einer Studie gibt, wurde zu jedem NOAK die jeweils größte Studie – stets verglichen gegenüber Dalteparin – ausgewertet. Die Studien wurden bzgl. ihrer Wirksamkeit, Sicherheit, fataler Blutungsraten, dem Risiko für gastrointestinale Blutungen (GIB) und sonstiger Unterschiede anhand deskriptiver Statistik analysiert. Unter Dalteparin ergab sich eine mittlere VTE-Rezidivrate von ca. 9% bei einem 6-monatigen Behandlungszeitraum. Alle 3 FXa-Inhibitoren waren gegenüber Dalteparin bezüglich der Wirksamkeit nicht unterlegen. Die VTE-Rezidivrate war bei mit Edoxaban und Apixaban behandelten Patienten um – 2,3% und bei Rivaroxaban um – 5,0% niedriger.

Bei der Sicherheit fanden sich – jeweils gegenüber Dalteparin – für Rivaroxaban und Edoxaban eine erhöhte Rate an schweren Blutungen (jeweils +2,4%); insbesondere war hierbei die Zahl GIB deutlich erhöht. Dagegen war für Apixaban die Zahl schwerer Blutungen, wie auch für verschiedene Blutungstypen inkl. GIB, nicht erhöht. In der Apixabanstudie war insgesamt die Rate von schweren GIB, die ca. 50% aller schweren Blutungen ausmachten, und die der klinisch-relevanten nicht schweren Blutungen, am niedrigsten. Die FXa-Inhibitoren sind der Standardtherapie mit Dalteparin in der VTE-Rezidivrate bei onkologischen Patienten nicht unterlegen. Die GIB-Rate scheint ein wichtiger prädiktiver Faktor für die Sicherheit dieser Substanzgruppe zu sein, sodass Tumorlokalisation, gastrointestinale Risikofaktoren und andere individuelle Kriterien in Zukunft stärker bei der Therapieentscheidung für oder gegen einen FXa-Inhibitor berücksichtigt werden sollten.

Clinical outcomes in patients receiving edoxaban or phenprocoumon for prevention of stroke in atrial fibrillation: a German real-world cohort study

Background

Appropriate and timely anticoagulant therapy with vitamin K antagonists (VKAs) or non-vitamin K oral antagonists (NOACs) is essential for stroke prevention in non-valvular atrial fibrillation (NVAF). Comparative data regarding effectiveness and safety for edoxaban vs phenprocoumon, the predominant VKA in Germany, are scarce.

Objectives

The study evaluates effectiveness and safety of edoxaban vs phenprocoumon in NVAF patients in a German real-world setting.

Methods

German statutory health insurance claims data of the Institute for Applied Health Research Berlin (InGef) Research Database from 2014 until 2019 were analyzed. In NVAF patients, new users of edoxaban and phenprocoumon were compared to assess effectiveness (stroke/systemic embolism (SE)) and safety (bleeding) during therapy. Hazard ratios (HR) were estimated through multiple outcome-specific cox proportional hazard models adjusting for baseline characteristics. Outcomes of geriatric patients were analyzed in subgroup analyses.

Results

Between 2015 and 2018, 7,975 and 13,319 NVAF patients newly initiated treatment with edoxaban or phenprocoumon. After adjusting for baseline confounders, the risk of stroke/SE (HR: 0.85, 95% CI: 0.70–1.02) was numerically but not significantly lower, while the risk of major bleeding (HR: 0.69, 95% CI: 0.58–0.81) was significantly lower for edoxaban. In the geriatric subgroups, homogenous results compared to the main analysis were obtained.

Conclusion

The results of this real-world analysis indicated better effectiveness and safety outcomes in patients with NVAF initiating edoxaban treatment compared to phenprocoumon. The findings confirm that the beneficial effects observed in the pivotal ENGAGE AF-TMI 48 trial can also be achieved in real-world use of edoxaban.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12959-022-00395-x.

Effectiveness and Safety of Apixaban in over 3.9 Million People with Atrial Fibrillation: A Systematic Review and Meta-Analysis

Background: There is a plethora of real-world data on the safety and effectiveness of direct-acting oral anticoagulants (DOACs); however, study heterogeneity has contributed to inconsistent findings. We compared the effectiveness and safety of apixaban with those of other direct-acting oral anticoagulants (DOACs) and vitamin K antagonists (VKA e.g., warfarin). Methods: A systematic review and meta-analysis was conducted retrieving data from PubMed, SCOPUS and Web of Science from January 2009 to December 2021. Studies that evaluated apixaban (intervention) prescribed for adults (aged 18 years or older) with AF for stroke prevention compared to other DOACs or VKAs were identified. Primary outcomes included stroke/systemic embolism (SE), all-cause mortality, and major bleeding. Secondary outcomes were intracranial haemorrhage (ICH) and ischaemic stroke. Randomised controlled trials and non-randomised trials were considered for inclusion. Results: In total, 67 studies were included, and 38 studies were meta-analysed. Participants taking apixaban had significantly lower stroke/SE compared to patients taking VKAs (relative risk (RR) 0.77, 95% confidence interval (CI) 0.64–0.93, I² = 94%) and dabigatran (RR 0.84, 95% CI 0.74–0.95, I² = 66%), but not to patients administered rivaroxaban. There was no statistical difference in mortality between apixaban and VKAs or apixaban and dabigatran. Compared to patients administered rivaroxaban, participants taking apixaban had lower mortality rates (RR 0.83, 95% CI 0.71–0.96, I² = 96%). Apixaban was associated with a significantly lower risk of major bleeding compared to VKAs (RR 0.58, 95% CI 0.52–0.65, I² = 90%), dabigatran (RR 0.79, 95% CI 0.70–0.88, I² = 78%) and rivaroxaban (RR 0.61, 95% CI 0.53–0.70, I² = 87%). Conclusions: Apixaban was associated with a better overall safety and effectiveness profile compared to VKAs and other DOACs.

Gastrointestinal Bleeding: a Cardiologist's Point of View

Oral anticoagulant therapy is widely used in different patients for the prevention and treatment of thromboembolic events: in atrial fibrillation, deep vein thrombosis/pulmonary embolism, acute coronary syndrome, in the early postoperative period after orthopedic surgery. Nowadays it is possible to use vitamin K antagonists (warfarin) as well as direct oral anticoagulants (DOAC): dabigatran, rivaroxaban, apixaban and edoxaban. The mai complication of any anticoagulant therapy is bleeding (gastrointestinal, intracranial, etc.), which seriously limits its usage. In this review the incidence of gastrointestinal bleeding (GIB) associated with oral anticoagulants intake was analyzed according to the results of both large randomized and postregistration trials. Furthermore, the effect of age on the risk of GIB development is discussed, and also aspects of the pathophysiology of gastrointestinal mucosa lesions in patients taking DOAC are considered.

Drugs in phase I and II clinical development for the prevention of stroke in patients with atrial fibrillation

INTRODUCTION

Atrial fibrillation is the most frequently diagnosed cardiac arrhythmia globally and is associated with ischemic stroke and heart failure. Patients with atrial fibrillation are typically prescribed long-term anticoagulants in the form of either vitamin K antagonists or non-vitamin K antagonist oral anticoagulants; however, both carry a potential risk of adverse bleeding.

AREAS COVERED

This paper sheds light on emerging anticoagulant agents which target clotting factors XI and XII, or their activated forms - XIa and XIIa, respectively, within the intrinsic coagulation pathway. The authors examined data available on PubMed, Scopus, and the clinical trials registry of the United States National Library of Medicine (www.clinicaltrials.gov).

EXPERT OPINION

Therapies targeting factors XI or XII can yield anticoagulant efficacy with the potential to reduce adverse bleeding. Advantages for targeting factor XI or XII include a wider therapeutic window and reduced bleeding. Long-term follow-up studies and a greater understanding of the safety and efficacy are required. Atrial fibrillation is a chronic disease and therefore the development of oral formulations is key.

Use, Persistence, Efficacy, and Safety of Apixaban in Patients with Non-Valvular Atrial Fibrillation in Unselected Patients in Germany. Results of the Prospective Apixaban in Atrial Fibrillation (APAF) Registry

INTRODUCTION

Apixaban has been shown to be superior to warfarin in patients with non-valvular atrial fibrillation in the randomized ARISTOTLE trial and its use is recommended in current guidelines. There are only scarce data about its use, efficacy, and safety in unselected patients in Germany.

METHODS AND RESULTS

The APAF registry is a prospective non-interventional study enrolling 5015 patients with non-valvular atrial fibrillation. Of these, 1349 (26.9%) patients were initially treated with apixaban and followed up at 3 and 12 months. The dose of apixaban used was 1 × 2.5 mg in 1.6%, 2 × 2.5 mg in 30.4%, and 2 × 5 mg daily in 68.0% of patients, respectively. Inappropriate underdosing of apixaban was observed in 22.3%, mostly in elderly patients with higher HAS-BLED Score and a history of bleeding. Persistence to apixaban after 1 year was 88.6%, while the dose was changed in 3.7% of patients. Switching to other NOACs or VKAs occurred in 5.1%. After 12 months, all-cause mortality was 5.0%, non-fatal stroke occurred in 0.4%, non-fatal myocardial infarction in 0.6%, ISTH major bleeding in 0.8%, moderate or minor bleeding in 4.3% of patients, respectively.

CONCLUSIONS

In this prospective experience in unselected patients with atrial fibrillation, persistence to apixaban was high, and efficacy and safety were comparable to the results in clinical trials, supporting its use in clinical practice.

Different Risk Profiles of European Patients Using Direct Oral Anticoagulants or Vitamin K Antagonists: a Rapid Review

Purpose of Review

We investigated the risk profiles of patients using direct oral anticoagulants (DOAC) or vitamin K antagonists (VKA) in European cohort studies to estimate the importance of potential (measured or unmeasured) confounding factors in analyses comparing these drugs. We searched MEDLINE and EMBASE (2008–2018) for relevant studies and extracted information on age, sex, comorbidity, Charlson comorbidity index, HAS-BLED score (assessing risk of bleeding) and CHA2DS2-VASc score (assessing risk of stroke).

Recent Findings

Overall, 66 studies with 2,808,757 patients were included. Most patients were from France (37%), Denmark (24%) and Germany (23%). In 56 studies (85%), the focus was on patients with atrial fibrillation. Of the 43 studies comparing DOAC with VKA users, 33% reported a higher and 16% a lower age of DOAC compared with VKA users. The mean age varied by about 1 year in most of these studies. Rivaroxaban was used in the widest age range. Patients with DOAC more often had a history of stroke or bleedings, and patients with VKA more often had a history of diabetes, renal failure, cancer, heart failure or other heart diseases. Most studies did not observe differences regarding the HAS-BLED score or the CHA2DS2-VASc score between groups.

Summary

Our review suggests that there are relevant differences in the risk profiles of DOAC versus VKA users and between users of individual DOACs. Reported HAS-BLED or CHA2DS2-VASc scores did not reflect these differences. These patterns require careful consideration in the interpretation of observational studies comparing the effectiveness and the risks of these drugs, also when comparing the results of studies conducted in different countries.

Risk of Major Gastrointestinal Bleeding With New vs Conventional Oral Anticoagulants: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

There is controversy over whether use of non-vitamin K antagonist oral anticoagulants (NOACs) associates with increased risk of major gastrointestinal bleeding (GIB) compared with conventional therapies (such as vitamin K antagonists or anti-platelet agents). We performed a systematic review and meta-analysis of data from randomized controlled trials and high-quality real-world studies.

METHODS

We performed a systematic search of the MEDLINE, EMBASE, Cochrane Library, and ClinicalTrials.gov Website databases (through Oct 12, 2018) for randomized controlled trials and high-quality real-world studies that reported major GIB events in patients given NOACs or conventional therapy. Relative risks (RRs) for randomized controlled trials and adjusted hazard ratios (aHRs) for real-world studies were calculated separately using random-effects models.

RESULTS

We analyzed data from 43 randomized controlled trials (183,752 patients) and 41 real-world studies (1,879,428 patients). The pooled major rates of GIB for patients on NOACs (1.19%) vs conventional treatment (0.92%) did not differ significantly (RR from randomized controlled trials, 1.09; 95% CI, 0.91-1.31 and aHR from real-world studies, 1.02; 95% CI, 0.94-1.10; P_interaction=.52). Rivaroxaban, but not other NOACs, was associated with an increased risk for major GIB (RR from randomized controlled trials, 1.39; 95% CI, 1.17-1.65 and aHR from real-world studies, 1.14; 95% CI, 1.04-1.23; P_interaction = .06). Analyses of subgroups, such as patients with different indications, dosage, or follow-up time, did not significantly affect results. Meta-regression analysis failed to detect any potential confounding to impact the primacy outcome.

CONCLUSIONS

In a systematic review and meta-analysis of data from randomized controlled trials and real-world studies, we confirmed that there is no significant difference in risk of major GIB between patients receiving NOACs vs conventional treatment. Rivaroxaban users had a 39% increase in risk for major GIB.

Left atrial appendage closure in patients with a reduced left ventricular ejection fraction: results from the multicenter German LAARGE registry

Background

Interventional left atrial appendage closure (LAAC) effectively prevents thromboembolic events in atrial fibrillation patients. Impaired left ventricular ejection fraction (LVEF) increases not only the thromboembolic risk but also the complication rates of cardiac interventions. The LAAC procedure’s benefit in patients with an impaired LVEF, therefore, has yet to be investigated.

Methods

LAARGE is a prospective, non-randomized registry depicting the clinical reality of LAAC in Germany. Procedure was conducted with different standard commercial devices, and follow-up period was one year. In the sense of an as-treated analysis, patients with started procedure and documented LVEF were selected from the whole database.

Results

619 patients from 37 centers were categorized into one of three groups: LVEF > 55% (56%), 36–55% (36%), and ≤ 35% (8%). Prevalence of cardiovascular comorbidity increased with LVEF reduction (p < 0.001 for trend). CHA₂DS₂-VASc score was 4.3, 4.8, and 5.1 (p < 0.001), and HAS-BLED score was 3.7, 4.1, and 4.2 (p < 0.001). Implantation success was consistently high (97.9%), rates of intra-hospital MACCE (0.5%), and other major complications (4.2%) were low (each p = NS). Kaplan–Meier estimation showed a decrease in survival free of stroke with LVEF reduction during one-year follow-up (89.3 vs. 87.0 vs. 79.8%; p = 0.067), a trend which was no longer evident after adjustment for relevant confounding factors. Rates of non-fatal strokes (0.4 vs. 1.1 vs. 0%) and severe bleedings (0.7 vs. 0.0 vs. 3.1%) were consistently low across all groups (each p = NS).

Conclusions

LVEF reduction neither influenced the procedural success nor the effectiveness and safety of stroke prevention by LAAC.

Trial Registration

ClinicalTrials.gov Identifier: NCT02230748

Graphic abstract

Electronic supplementary material

The online version of this article (10.1007/s00392-020-01627-8) contains supplementary material, which is available to authorized users.

Real-life behaviour of direct oral anticoagulants in a Spanish cohort with non-valvular atrial fibrillation: Refase Registry

Aim: To analyse the effectiveness and safety of DOAC (direct oral anticoagulants) in non-valvular atrial fibrillation (NVAF) patients attending clinical practice.Methods: Retrospective study of AF patients who started treatment with DOAC from January 1, 2013 to December 31, 2016 in three Spanish hospitals. Mean follow-up was 1.6 years. The primary outcomes were rates of all-cause death, ischaemic stroke, and bleeding. These outcomes were also studied depending on correct dosage adjustment and standard/adjusted dose.Results: The study included 2494 patients (age = 76.0 ± 9.5 years, CHA₂DS₂-VASc = 4.0 ± 1.6). The most prescribed DOAC was rivaroxaban (41.1%). Patients taking dabigatran were the youngest (mean age = 73.1 ± 10.3 years), with better kidney function (mean CrCl = 80.6 ± 35.8 ml/min) and lower CHA₂DS₂-VASc (3.7 ± 1.4) and HAS-BLED (2.1 ± 0.9) scores. Patients taking apixaban were the oldest, and had the highest CHA2DS2-VASc and HAS-BLED scores (4.3 ± 1.6 and 2.6 ± 0.9, respectively). Rates of stroke/major bleeding/intracranial bleeding were 1.8/3.0/0.3 events per 100 patient-years, respectively, with no differences among DOAC. Based on dose adjustment according to technical data, it was observed that 517 patients (23.5%) received DOAC doses inconsistent with labelling (p < .001) and, within this group, under-dosed patients had a higher death rate although it did not reach a significant result after multivariate adjustment.Conclusions: The results of safety and efficacy are very similar to those of other previously published national registries. There were no differences among the different types of DOAC regarding outcomes. However, it was found that people taking the adjusted dose of the drug seemed to have a higher risk of death. A non-negligible proportion of patients received DOAC doses inconsistent with labelling (mostly underdose).

The 2018 European Heart Rhythm Association Practical Guide on the use of non-vitamin K antagonist oral anticoagulants in patients with atrial fibrillation

The current manuscript is the second update of the original Practical Guide, published in 2013 [Heidbuchel et al. European Heart Rhythm Association Practical Guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation. Europace 2013;15:625-651; Heidbuchel et al. Updated European Heart Rhythm Association Practical Guide on the use of non-vitamin K antagonist anticoagulants in patients with non-valvular atrial fibrillation. Europace 2015;17:1467-1507]. Non-vitamin K antagonist oral anticoagulants (NOACs) are an alternative for vitamin K antagonists (VKAs) to prevent stroke in patients with atrial fibrillation (AF) and have emerged as the preferred choice, particularly in patients newly started on anticoagulation. Both physicians and patients are becoming more accustomed to the use of these drugs in clinical practice. However, many unresolved questions on how to optimally use these agents in specific clinical situations remain. The European Heart Rhythm Association (EHRA) set out to coordinate a unified way of informing physicians on the use of the different NOACs. A writing group identified 20 topics of concrete clinical scenarios for which practical answers were formulated, based on available evidence. The 20 topics are as follows i.e., (1) Eligibility for NOACs; (2) Practical start-up and follow-up scheme for patients on NOACs; (3) Ensuring adherence to prescribed oral anticoagulant intake; (4) Switching between anticoagulant regimens; (5) Pharmacokinetics and drug-drug interactions of NOACs; (6) NOACs in patients with chronic kidney or advanced liver disease; (7) How to measure the anticoagulant effect of NOACs; (8) NOAC plasma level measurement: rare indications, precautions, and potential pitfalls; (9) How to deal with dosing errors; (10) What to do if there is a (suspected) overdose without bleeding, or a clotting test is indicating a potential risk of bleeding; (11) Management of bleeding under NOAC therapy; (12) Patients undergoing a planned invasive procedure, surgery or ablation; (13) Patients requiring an urgent surgical intervention; (14) Patients with AF and coronary artery disease; (15) Avoiding confusion with NOAC dosing across indications; (16) Cardioversion in a NOAC-treated patient; (17) AF patients presenting with acute stroke while on NOACs; (18) NOACs in special situations; (19) Anticoagulation in AF patients with a malignancy; and (20) Optimizing dose adjustments of VKA. Additional information and downloads of the text and anticoagulation cards in different languages can be found on an EHRA website (www.NOACforAF.eu).

Outcome reporting from clinical trials of non-valvular atrial fibrillation treated with traditional Chinese medicine or Western medicine: a systematic review

OBJECTIVES

To examine variation in outcomes, outcome measurement instruments (OMIs) and measurement times in clinical trials of non-valvular atrial fibrillation (NVAF) and to identify outcomes for prioritisation in developing a core outcome set (COS) in this field.

DESIGN

This study was a systematic review.

DATA SOURCES

Clinical trials published between January 2015 and March 2019 were obtained from PubMed, the Cochrane Library, Web of Science, Wanfang Database, the China National Knowledge Infrastructure and SinoMed.

ELIGIBILITY CRITERIA

Randomised controlled trials (RCTs) and observational studies were considered. Interventions included traditional Chinese medicine and Western medicine. The required treatment duration or follow-up time was ≥4 weeks. The required sample size was ≥30 and≥50 in each group in RCTs and observational studies, respectively. We excluded trials that aimed to investigate the outcome of complications of NVAF, to assess the mechanisms or pharmacokinetics, or for which full text could not be acquired.

DATA EXTRACTION AND SYNTHESIS

The general information and outcomes, OMIs and measurement times were extracted. The methodological and outcome reporting quality were assessed. The results were analysed by descriptive analysis.

RESULTS

A total of 218 articles were included from 25 255 articles. For clinical trials of antiarrhythmic therapy, 69 outcomes from 16 outcome domains were reported, and 28 (31.82%, 28/88) outcomes were reported only once; the most frequently reported outcome was ultrasonic cardiogram. Thirty-one outcomes (44.93%, 31/69) were provided definitions or OMIs; the outcome measurement times ranged from 1 to 20 with a median of 3. For clinical trials of anticoagulation therapy, 82 outcomes from 18 outcome domains were reported; 38 (29.23%, 38/130) outcomes were reported only once. The most frequently reported outcome was ischaemic stroke. Forty (48.78%, 40/82) outcomes were provided OMIs or definitions; and the outcome measurement times ranged from 1 to 27 with a median of 8.

CONCLUSION

Outcome reporting in NVAF is inconsistent. Thus, developing a COS that can be used in clinical trials is necessary.

Drug interactions with oral anticoagulants in German nursing home residents: comparison between vitamin K antagonists and non-vitamin K antagonist oral anticoagulants based on two nested case-control studies

BACKGROUND

Vitamin K antagonists (VKAs) are susceptible to drug-drug interactions. Non-VKA oral anticoagulants (NOACs) have a decreased sensitivity to pharmacokinetic interactions and might be therefore considered superior in patients treated with multiple drugs. The objective of this study was to compare the risk of serious bleeding associated with interacting drugs in German nursing home residents treated with VKA or NOAC.

METHODS

Using claims data of new nursing home residents aged ≥ 65 years (2010-2014) we conducted separate nested case-control analyses within two cohorts of patients treated with VKA or NOAC, respectively. Cases were defined as patients hospitalized for serious bleeding. For each case, up to 20 controls were selected by risk-set sampling. Conditional logistic regression was used to obtain confounder-adjusted odds ratios (aORs) and 95% confidence intervals (CI) for the risk of bleeding associated with VKA or NOAC use and interacting drugs compared with the use of the respective oral anticoagulant alone.

RESULTS

Among 127,227 new nursing home residents, 16,804 patients received oral anticoagulation. Based on 372 cases and 7281 matched controls, the highest risk of bleeding in VKA users was observed for the concomitant use of antibiotics (aOR 3.00; CI 2.11-4.27) vs. VKA use alone, followed by non-steroidal anti-inflammatory drugs (1.66; 1.13-2.43). Among 243 NOAC cases and 4776 matched controls, elevated risks for bleeding were observed for the use of heparins (2.05; 1.25-3.36) and platelet inhibitors (1.92; 1.36-2.72).

CONCLUSIONS

Concomitant medication needs to be prescribed cautiously and monitored closely in nursing home residents treated with oral anticoagulants.

Safety and effectiveness of apixaban in Japanese patients with nonvalvular atrial fibrillation in clinical practice: A regulatory postmarketing surveillance, the STANDARD study

BACKGROUND

Apixaban, a non-vitamin K oral anticoagulant (NOAC), was approved in Japan in 2012 for the prevention of thromboembolic events in patients with nonvalvular atrial fibrillation (NVAF). However, the safety and effectiveness of apixaban in clinical practice have not yet been elucidated thoroughly among Japanese NVAF patients.

METHODS

A postmarketing surveillance study was conducted to determine the safety and effectiveness of apixaban. Patients were followed-up for 104 weeks. Outcome events included adverse drug reactions (ADRs), hemorrhages, and thromboembolic events (ischemic stroke, systemic embolism [SE], and transient ischemic attack [TIA]).

RESULTS

Among 6306 NVAF patients in the safety analysis set (age, 74.5 ± 10.1 years; women, 41.1%; and CHADS 2 score, 2.0 ± 1.4), 3600 patients (57.1%) received the standard dose (5 mg twice daily) and 2694 (42.7%) received a reduced dose (2.5 mg twice daily) of apixaban. ADRs occurred in 604 patients (9.58%), with the most common being epistaxis (0.86%), subcutaneous hemorrhage (0.67%), and hematuria (0.57%). Incidence rate of any hemorrhages and major hemorrhage was 5.52% per year and 2.36% per year, respectively. Incidence rate of ischemic stroke/SE/TIA was 1.00% per year among 6286 patients in the effectiveness analysis set. Among three subgroups (3106 apixaban initiators, 2038 patients switched from warfarin, and 1118 patients switched from other NOACs), incidence rates of major hemorrhage (P = 0.221 for trend) and ischemic stroke/SE/TIA (P = 0.686 for trend) were comparable.

CONCLUSIONS

No new safety signals of apixaban were identified in Japanese NVAF patients. Safety and effectiveness of apixaban were consistent with those in the ARISTOTLE study.

Real-world safety and efficacy of WATCHMAN LAA closure at one year in patients on dual antiplatelet therapy: results of the DAPT subgroup from the EWOLUTION all-comers study

AIMS

The study aimed to confirm the efficacy and safety of WATCHMAN LAA closure in atrial fibrillation patients unsuitable for oral anticoagulation.

METHODS AND RESULTS

The EWOLUTION registry prospectively collects all clinical data on 1,005 European patients implanted with a WATCHMAN device. Following the procedure, 605 patients (60.2%) received dual antiplatelet therapy according to the local standard; DAPT was discontinued in 85% of patients within one year. CHA2DS2-VASc and HAS-BLED scores were 4.61.6 and 2.41.2, respectively. The periprocedural SAE rate was 3.3% (2.0% major adverse cardiac events), mostly resolving without sequelae. Device embolisation or pericardial effusion occurred in one (0.2%) and two (0.3%) patients, respectively. TEE (median 62 days post implant, IQR: 47-97) confirmed effective sealing (no leak >5 mm) in 99.2% of patients. Device thrombus was present in 22 patients (4.0%), one patient developed a stroke. One-year mortality in the DAPT group was 9.6% (N=58) reflecting the advanced age and comorbidities in this population. The ischaemic stroke rate at one year was 1.4% (expected based on CHA2DS2-VASc: 7.5%), none fatal. The major bleeding rate was 2.5%, or 2.1% excluding periprocedural events (expected rate on VKA based on HAS-BLED: 5.1%).

CONCLUSIONS

LAA closure with the WATCHMAN device followed by DAPT therapy in a high-risk patient population is safe. At one year, the intervention is associated with a substantial risk reduction regarding ischaemic stroke and major bleeding compared to the expected rate based on CHA2DS2-VASc and HAS-BLED scores.

Facing real-life with direct oral anticoagulants in patients with nonvalvular atrial fibrillation: outcomes from the first observational and prospective study in a Spanish population

Aim: To analyze the effectiveness and safety of direct oral anticoagulants (DOACs) in atrial fibrillation (AF) patients attended in clinical practice. Methods: Observational and prospective study of AF patients that started treatment with DOACs. Results: 1443 patients (age 77.2 ± 9.7 years, CHA2DS2-VASc = 4.1 ± 1.5) were included. 46.0% were taking rivaroxaban, 24.4% dabigatran, 22.5% apixaban and 7.1% edoxaban. Patients taking dabigatran were younger, had lower CHA2DS2-VASc and lesser renal insufficiency. Patients taking apixaban had higher CHA2DS2-VASc and more renal insufficiency. Rates of stroke/major bleeding/intracranial bleeding were 0.7/1.3/0.2 events/100 patient-years, respectively. Conclusion: This was the first prospective study that analyzed the use of all DOACs in AF patients in Spain, showing a good profile in terms of safety and effectiveness in accordance with pivotal studies.

Major bleeding with antithrombotic agents: a 2012-2015 study using the French nationwide Health Insurance database linked to emergency department records within five areas - rationale and design of SACHA study

Bleeding represents the most recognized and feared complications of antithrombotic drugs including oral anticoagulants. Previous studies showed inconsistent results on the safety profile. Among explanations, bleeding definition could vary and classification bias exists related to the lack of medical evaluation. To quantify the risk of major haemorrhagic event and event-free survival associated with antithrombotic drugs (vitamin K antagonist [VKA], non-VKA anticoagulant [NOAC], antiplatelet agent, parenteral anticoagulant) in 2012-2015, we linked the French nationwide Health Insurance database (SNIIRAM) with a local 'emergency database' (clinical and biological data collected in clinical records). In the VKA-NOAC comparison, a Cox regression analysis will be used to estimate the hazard ratio of major haemorrhagic event adjusted on gender, modified HAS-BLED score and comorbidities. A distinction on the type of major haemorrhagic event (intracranial, gastrointestinal and other haemorrhagic events) was made. We present here the study protocol and the database linkage results. Using six linkage keys, among 3 837 557 hospital visits identified in SNIIRAM, 5264 have been matched with a major haemorrhagic event identified in the 'emergency database', thus clinically confirmed. The 1090 unmatched haemorrhagic events could be explained by the fact that patients were not extracted in the SNIIRAM database (patients living in accommodation establishment with internal use of pharmacy, military people with specific insurance…). We showed the value of SNIIRAM enrichment with a clinical database, a necessary step to categorize haemorrhagic events by a clinically relevant definition and medical validation; it will allow to estimate more accuracy each type of haemorrhagic event.

Direct oral anticoagulants and vitamin K antagonists are linked to differential profiles of cardiac function and lipid metabolism

BACKGROUND

Experimental data indicate that direct acting oral anticoagulants (DOAC) and vitamin K antagonists (VKA) may exert differential effects on cardiovascular disease.

METHODS

Data from the prospective, observational, single-center MyoVasc Study were used to examine associations of DOAC as compared to VKA with subclinical markers of cardiovascular disease, cardiac function, and humoral biomarkers in heart failure (HF).

RESULTS

Multivariable analysis adjusted for age, sex, traditional cardiovascular risk factors, comorbidities, and medications with correction for multiple testing demonstrated that DOAC therapy was among all investigated parameters an independent significant predictor of better diastolic function (E/E': β - 0.24 [- 0.36/- 0.12]; P < 0.0001) and higher levels of ApoA1 (β + 0.11 g/L [0.036/0.18]; P = 0.0038) compared to VKA therapy. In propensity score-weighted analyses, the most pronounced differences between DOAC and VKA-based therapy were also observed for E/E' (∆ - 2.36) and ApoA1 (∆ + 0.06 g/L). Sensitivity analyses in more homogeneous subsamples of (i) individuals with AF and (ii) individuals with asymptomatic HF confirmed the consistency and robustness of these findings. In the comparison of factor IIa and Xa-directed oral anticoagulation, no differences were observed regarding cardiac function (E/E' ratio: β_{IIa inhibitor} - 0.22 [- 0.36/- 0.08] vs. β_{Xa inhibitor} - 0.24 [- 0.37/- 0.11]) and lipid metabolism (ApoA1: β_{IIa inhibitor} 0.10 [0.01/0.18] vs. β_{Xa inhibitor} 0.12 [0.04/0.20]) compared to VKA therapy.

CONCLUSION

This study provides the first evidence for differential, non-conventional associations of oral anticoagulants on cardiac function and lipid metabolism in humans. The potentially beneficial effect of DOACs in the highly vulnerable population of HF individuals needs to be further elucidated and may have implications for individually tailored anticoagulation therapy.

LMU Munich: platelet inhibition novel aspects on platelet inhibition and function

A core research area in the Department of Cardiology at Ludwig-Maximilians-University (LMU) Munich focuses on antiplatelet therapy, its translational aspects, and its underlying mechanism with respect to platelet physiology. We are conducting a broad range of investigator-initiated clinical trials (phase II-IV) and preclinical studies on the topic of antithrombotic therapy for percutaneous coronary intervention patients, platelet activation, and reactivity as well as on novel inhibitors of platelet adhesion. Just recently, we completed the large multi-centre investigator-initiated TROPICAL-ACS trial on guided early de-escalation of antiplatelet treatment in acute coronary syndrome (ACS) patients (Sibbing et al. in Lancet 390:1747-1757, 2017; Sibbing et al. in Thromb Haemost 117:1240-1248), done at 33 sites in Europe. Furthermore, besides other ongoing clinical studies, we initiated and are currently recruiting patients for the multi-centre randomized APixaban versus PhenpRocoumon in Patients With ACS and AF: APPROACH-ACS-AF study as well as for the multi-centre phase II randomized, double-blind, placebo-controlled study of revacept in Patients With Stable Coronary Artery Disease (Revacept/CAD/02) trial.

Sustained atrial fibrillation increases the risk of anticoagulation-related bleeding in heart failure

BACKGROUND

Oral anticoagulation therapy in individuals with atrial fibrillation (AF) reduces the risk of thromboembolic events at cost of an increased bleeding risk. Whether anticoagulation-related outcomes differ between patients with paroxysmal and sustained AF receiving anticoagulation is controversially discussed.

METHODS

In the present analysis of the prospective multi-center cohort study thrombEVAL, the incidence of anticoagulation-related adverse events was analyzed according to the AF phenotype. Information on outcome was centrally recorded over 3 years, validated via medical records and adjudicated by an independent review panel. Study monitoring was provided by an independent institution.

RESULTS

Overall, the sample comprised 1089 AF individuals, of whom n = 398 had paroxysmal AF and n = 691 experienced sustained AF. In Cox regression analysis with adjustment for potential confounders, sustained AF indicated an independently elevated risk of clinically relevant bleeding compared to paroxysmal AF [hazard ratio (HR) 1.40 (1.02; 1.93); P = 0.038]. For clinically relevant bleeding, a significant interaction of the pattern of AF type with concomitant heart failure (HF) was detected: HR_HF 2.45 (1.51, 3.98) vs. HR_{no HF} 0.85 (0.55, 1.34); P_interaction = 0.003. In HF patients, sustained AF indicated also an elevated risk of major bleeding [HR 2.25 (1.26, 4.20); P = 0.006]. A simplified HAS-BLED score incorporating only information on age (> 65 years), bleeding history, and HF with sustained AF demonstrated better discriminative performance for clinically relevant bleeding than the original version: AUC_HAS-BLED: 0.583 vs. AUC_{simplifiedHAS-BLED}: 0.642 (P = 0.004).

CONCLUSIONS

In HF patients receiving oral anticoagulation, sustained AF indicates a substantially elevated risk of bleeding.

CLINICAL TRIAL REGISTRATION

https://clinicaltrials.gov , identifier: NCT01809015.

Rivaroxaban does not influence hemorrhagic transformation in a diabetes ischemic stroke and endovascular thrombectomy model

Managing endovascular thrombectomy (ET) in diabetic ischemic stroke (IS) with novel anticoagulants is challenging due to putative risk of intracerebral hemorrhage. The study evaluates increased hemorrhagic transformation (HT) risk in Rivaroxaban-treated diabetic rats post ET. Diabetes was induced in male Sprague-Dawley rats by intraperitoneal injection of 60 mg/kg streptozotocin. After 4-weeks, rats were pretreated orally with 30 mg/kg Rivaroxaban/saline; prothrombin time was monitored. IS and ET was induced after 1 h, by thread-induced transient middle cerebral artery occlusion (tMCAO) that mimicked mechanical ET for proximal MCA occlusion at 60 min. After 24 h reperfusion, infarct volumes, HT, blood-brain barrier (BBB) permeability, tight junction at peri-ischemic lesion and matrix metalloproteinase-9 (MMP-9) activity was measured. Diabetic rats seemed to exhibit increased infarct volume and HT at 24 h after ET than normal rats. Infarct volumes and functional outcomes did not differ between Rivaroxaban and diabetic control groups. A significant increase in HT volumes and BBB permeability under Rivaroxaban treatment was not detected. Compared to diabetic control group, neither the occludin expression was remarkably lower in the Rivaroxaban group nor the MMP-9 activity was higher. Together, Rivaroxaban does not increase HT after ET in diabetic rats with proximal MCA occlusion, since Rivaroxaban has fewer effects on post-ischemic BBB permeability.

Oral Anticoagulation in Chronic Kidney Disease and Atrial Fibrillation

BACKGROUND

Cardiological societies recommend, in their guidelines, that patients with atrial fibrillation and an intermediate (or higher) risk of stroke and systemic embolization should be treated with oral anticoagulant drugs. For patients who do not have mitral valve stenosis or a mechanical valve prosthesis, non-vitamin-K dependent oral anticoagulants (NOAC) are preferred over vitamin K antagonists (VKA) for this purpose. It is unclear, however, whether patients with chronic kidney disease and atrial fibrillation benefit from oral anticoagulation to the same extent as those with normal kidney function. It is also unclear which of the two types of anti - coagulant drug is preferable for patients with chronic kidney disease; NOAC are, in part, renally eliminated.

METHODS

This review is based on pertinent publications retrieved by a selective literature search, and on international guidelines.

RESULTS

Current evidence suggests that patients with atrial fibrillation who have chronic kidney disease with a glomerular filtration rate (GFR) above 15 mL/ min/1.73 m² should be treated with an oral anticoagulant drug if they have an at least intermediate risk of embolization, as assessed with the CHA2DS2-VASc score. For patients with advanced chronic kidney disease (GFR from 15 to 29 mL/ min/1.73 m²), however, this recommendation is based only on registry studies. For dialysis patients with atrial fibrillation, decisions whether to give oral anticoagulant drugs should be taken on an individual basis, in view of the elevated risk of hemorrhage and the unclear efficacy of such drugs in these patients. The subgroup analyses of the NOAC approval studies show that, for patients with atrial fibrillation and chronic kidney disease with a creatinine clearance of >25-30 mL/min, NOAC should be given in preference to VKA, as long as the patient does not have mitral valve stenosis or a mechanical valve prosthesis. For those whose creatinine clearance is less than 25 mL/min, the relative merits of NOAC versus VKA are still debated.

CONCLUSION

The cardiological societies' recommendation that patients with atrial fibrillation should be given oral anticoagulant drugs applies to the majority of such patients who also have chronic kidney disease.

Antithrombotic therapy in patients with non-valvular atrial fibrillation undergoing percutaneous coronary intervention: should we change our practice after the PIONEER AF-PCI and RE-DUAL PCI trials?

The number of patients with atrial fibrillation undergoing percutaneous coronary intervention (PCI) is increasing. Since these patients have a CHA₂DS₂-VASc score of 1 or higher, they should be treated with oral anticoagulation to prevent stroke. However, combination therapy with oral anticoagulation for prevention of embolic stroke and dual platelet inhibition for prevention of coronary thrombosis significantly increases bleeding complications. The optimal combination, intensity and duration of antithrombotic combination therapy is still not known. In the rather small randomized WOEST trial, the combination of a vitamin K antagonist (VKA) and clopidogrel decreased bleeding compared to the conventional triple therapy with VKA, clopidogrel and aspirin. In the PIONEER AF-PCI trial, two rivaroxaban-based treatment regimens significantly reduced bleeding complications compared to conventional triple therapy without increasing embolic or ischemic complications following PCI. Dual therapy with rivaroxaban and clopidogrel appeared to provide an optimal risk-benefit ratio. In the RE-DUAL PCI trial, dual therapy with dabigatran also reduced bleeding complications compared to conventional triple therapy. With respect to the composite efficacy end point of thromboembolic events (myocardial infarction, stroke, or systemic embolism), death, or unplanned revascularization dabigatran-based dual therapy was non-inferior to VKA-based triple therapy. The upcoming trials AUGUSTUS with apixaban and ENTRUST-PCI with edoxaban will further examine the use of NOACs in this setting. While recent guidelines recommend NOAC-based dual therapy in only a subset of patients (those who are at increased risk of bleeding), the available data now suggest that this should be the preferred choice for the majority of patients. Adding aspirin to this primary choice for up to 4 weeks in patients at especially high ischemic risk would likely prevent atherothrombotic events, but this needs further investigation. Taken together, it is time to adjust our practice and move to dual therapy consisting of a NOAC plus clopidogrel in most patients.

Direct Oral Anticoagulants Versus Vitamin K Antagonists in Real-life Patients With Atrial Fibrillation. A Systematic Review and Meta-analysis

INTRODUCTION AND OBJECTIVES

To assess the effectiveness of direct oral anticoagulants vs vitamin K antagonists in real-life patients with atrial fibrillation.

METHODS

A systematic review was performed according to Cochrane methodological standards. The results were reported according to the PRISMA statement. The ROBINS-I tool was used to assess risk of bias.

RESULTS

A total of 27 different studies publishing data in 30 publications were included. In the studies with a follow-up up to 1 year, apixaban (HR, 0.93; 95%CI, 0.71-1.20) and dabigatran (HR, 0.95; 95%CI, 0.80-1.13) did not significantly reduce the risk of ischemic stroke vs warfarin, whereas rivaroxaban significantly reduced this risk (HR, 0.83; 95%CI, 0.73-0.94). Apixaban (HR, 0.66; 95%CI, 0.55-0.80) and dabigatran (HR, 0.83; 95%CI, 0.70-0.97) significantly reduced the major bleeding risk vs warfarin, but not rivaroxaban (HR, 1.02; 95%CI, 0.95-1.10), although with a high statistical heterogeneity among studies. Apixaban (HR, 0.56; 95%CI, 0.42-0.73), dabigatran (HR, 0.45; 95%CI, 0.39-0.51), and rivaroxaban (HR, 0.66; 95%CI, 0.49-0.88) significantly reduced the risk of intracranial bleeding vs warfarin. Reduced doses of direct oral anticoagulants were associated with a slightly better safety profile, but with a marked reduction in stroke prevention effectiveness.

CONCLUSIONS

Data from this meta-analysis suggest that, vs warfarin, the stroke prevention effectiveness and bleeding risk of direct oral anticoagulants may differ in real-life patients with atrial fibrillation.

Apixaban 5 and 2.5 mg twice-daily versus warfarin for stroke prevention in nonvalvular atrial fibrillation patients: Comparative effectiveness and safety evaluated using a propensity-score-matched approach

Prior real-world studies have shown that apixaban is associated with a reduced risk of stroke/systemic embolism (stroke/SE) and major bleeding versus warfarin. However, few studies evaluated the effectiveness and safety of apixaban according to its dosage, and most studies contained limited numbers of patients prescribed 2.5 mg twice-daily (BID) apixaban. Using pooled data from 4 American claims database sources, baseline characteristics and outcomes for patients prescribed 5 mg BID and 2.5 mg BID apixaban versus warfarin were compared. After 1:1 propensity-score matching, 31,827 5 mg BID apixaban-matched warfarin patients and 6600 2.5 mg BID apixaban-matched warfarin patients were identified. Patients prescribed 2.5 mg BID apixaban were older, had clinically more severe comorbidities, and were more likely to have a history of stroke and bleeding compared with 5 mg BID apixaban patients. Compared with warfarin, 5 mg BID apixaban was associated with a lower risk of stroke/SE (hazard ratio [HR]: 0.70, 95% confidence interval [CI]: 0.60–0.81) and major bleeding (HR: 0.59, 95% CI: 0.53–0.66). Compared with warfarin, 2.5 mg BID apixaban was also associated with a lower risk of stroke/SE (HR: 0.63, 95% CI: 0.49–0.81) and major bleeding (HR: 0.59, 95% CI: 0.49–0.71). In this real-world study, both apixaban doses were assessed in 2 patient groups differing in age and clinical characteristics. Each apixaban dose was associated with a lower risk of stroke/SE and major bleeding compared with warfarin in the distinct population for which it is being prescribed in United States clinical practice.

Trial registration: Clinicaltrials.Gov Identifier: NCT03087487.

[Oral anticoagulation and platelet inhibition after atrial appendage occlusion]

In Europe left atrial appendage occluders (LAAO) are most frequently used in patients with contraindications for oral anticoagulation (OAC); therefore, the classical therapeutic OAC scheme from the PROTECT-AF trial (vitamin K antagonist plus acetylsalicylic acid) is usually changed to dual anti-platelet therapy (DAPT) after implantation of a Watchman® or Amulet® LAAO (St. Jude Medical/Abbott, Eschborn, Germany). For many years, patients with an LAAO received DAPT for 1-6 months. The current standard comprises DAPT for 3 months, followed by permanent acetylsalicylic acid monotherapy if the transesophageal echocardiogram excludes a thrombus at the site of the LAAO. In patients with high risk of bleeding, anti-platelet therapy can be stopped at 3 months after an individual risk-benefit calculation. There are no randomized studies on the risk of bleeding and stroke/embolism in patients with an LAA occluder under DAPT versus OAC. Experience from the EWOLUTION registry shows that NOACs may be used as an alternative with low bleeding and thrombus risks. In patients with a suboptimal implantation result, thrombus on the LAAO or specific risk factors, variations of the standard scheme have to be applied and if necessary lifelong DAPT or NOAC therapy has to be used. Thrombi on the LAAO occur in approximately 4-6% of patients and are associated with a very low short-term stroke risk.

Anticoagulation in atrial fibrillation : Current evidence and guideline recommendations

Atrial fibrillation (AF) is the most frequently encountered sustained arrhythmia with a prevalence of 0.5-10%, depending predominantly on age. The arrhythmia is associated with significant morbidity and mortality, mainly due to thromboembolic events including stroke and systemic embolisms. These complications can be effectively prevented with anticoagulation therapy either with vitamin K antagonists (VKA) or with non-vitamin K antagonists (NOAC). VKA therapy is effective in preventing strokes but these medications are difficult to use, are associated with significant bleeding risk, and have pharmacokinetic/dynamic properties that make their use cumbersome. NOACs-either factor II or factor Xa inhibitors-have been developed over the past two decades and have been tested against VKA in large randomized controlled trials. This trial evidence was complemented more recently by increasing real-world data comprising several 100,000 patients. Finally, NOACs have been examined for their use in specific clinical situations, for example, in patients undergoing cardioversion, catheter ablation, or coronary interventions. In all of these clinical scenarios, NOACs have been similarly effective or-in many instances-even superior to treatment with VKA. Recent guidelines, therefore, recommend NOAC therapy for stroke prevention in AF as first-line therapy.

Meta-Analysis of Effectiveness and Safety of Oral Anticoagulants in Atrial Fibrillation With Focus on Apixaban

We performed a meta-analysis of data on the effectiveness and safety of apixaban compared with other oral anticoagulants (warfarin or rivaroxaban or dabigatran or edoxaban) for stroke prevention in atrial fibrillation (AF) in different settings of randomized controlled trials, real-world studies, and radiofrequency ablation (RFA). Thirty studies were searched in PubMed, the Cochrane Library, and Clinicaltrials.gov databases reporting comparative effectiveness and safety of apixaban with warfarin (n = 23), rivaroxaban (n = 12), dabigatran (n = 13), or edoxaban (n = 2) for stroke prevention in AF. In real-world estimates, apixaban was similar to warfarin for the prevention of stroke or systematic thromboembolism (hazard ratio 0.93, 95% CI 0.71 to 1.14, I² = 82.9%, N = 7), and safer than warfarin in the risks of major bleeding (hazard ratio 0.62, 95% CI 0.54 to 0.70, I² = 18.7%, N = 9) in patients with AF. The risk of stroke or thromboembolism with apixaban was similar to rivaroxaban, dabigatran, and edoxaban in the settings of real-world studies and RFA. Major bleeding with apixaban was generally lower than rivaroxaban (relative risks 0.45, 95% CI 0.38 to 0.53, I² = 0%, N = 5) and similar to dabigatran in real-world studies (relative risks 1.44, 95% CI 0.33 to 6.30, I² = 97.7%, N = 5), but similar to rivaroxaban, dabigatran, and edoxaban in RFA. In conclusion, our meta-analysis provides a comprehensive estimate of the effectiveness and safety of apixaban compared with other oral anticoagulants (warfarin, rivaroxaban, dabigatran, and edoxaban) in patients with AF in different settings of randomized controlled trial, real-world studies, and RFA.

Real-world Data and Recommended Dosage of Non-vitamin K Oral Anticoagulants for Korean Patients

Regulatory approvals of non-vitamin K antagonist oral anticoagulants (NOACs) have been based on large randomized phase III trials evaluating dabigatran, rivaroxaban, apixaban, or edoxaban relative to warfarin for atrial fibrillation (AF). The results of the trials showed that all NOACs were at least non-inferior to warfarin in the prevention of stroke/thromboembolism and showed lower rates of intracranial bleeding than those associated with warfarin. However, the trials were designed differently, varied in the inclusion/exclusion criteria, and used either one dose or a low/high dose of the NOAC drug. Some of these differences have challenged the ability to directly compare various NOACs, and comparative data on effectiveness and intracranial bleeding are sparse in "real-world" patients. Real-world data complement data from large randomized phase III trials by providing new aspects of the "real-world" absolute risks of ischemic and hemorrhagic stroke associated with NOACs vs. warfarin. Moreover, "real-world" fragile patients might have been included (e.g., patients with increased risk of bleeding, liver disease, and chronic kidney disease), although these patients would be less represented in trials. This paper introduces recently published real-world data of NOACs and further suggests the recommended dosage of NOACs for Korean patients.