scholarly journals Measurement of Anticoagulation in Patients on Dabigatran, Rivaroxaban and Apixaban Therapy by Novel Automated Thrombelastography

TH Open ◽  
2021 ◽  
Author(s):  
Ramin Artang ◽  
Joao Dias ◽  
Mark Walsh ◽  
Kevin P Bliden ◽  
Jørn Dalsgaard Nielsen ◽  
...  
Keyword(s):  
Linear Correlation ◽  
Oral Anticoagulants ◽  
Plasma Concentrations ◽  
Factor Xa ◽  
High Sensitivity ◽  
Thrombin Inhibitor ◽  
Urgent Surgery ◽  
Lower Drug ◽  
Direct Acting ◽  
Sensitivity Specificity

Background: Direct-acting oral anticoagulants (DOACs) do not require monitoring. Measurement of DOAC effect would be useful in the event of bleeding, trauma, and thromboembolism while on anticoagulation. We evaluated the effectiveness of the investigational DOAC assays on the TEG®6s Hemostasis Analyzer to assess the anticoagulant effect of DOACs in patients treated for atrial fibrillation or DVT. Methods: Patients on treatment for a minimum of 7 days with standard doses of dabigatran, rivaroxaban and apixaban were included. DOAC plasma concentrations and TEG®6s R-time were measured and correlated. The sensitivity, specificity and negative predictive value (NPV) of R-time to detect DOAC concentrations of ≥ 30, ≥ 50 and ≥ 100 ng/mL were calculated. Results: 189 Subjects were included, (n=50) on apixaban, (n= 62) on rivaroxaban, (n=53) on dabigatran and (n=24) on no DOAC were studied. Using the direct thrombin inhibitor (DTI) channel, R-time demonstrated strong linear correlation with dabigatran levels (r = 0.93, p < 0.0001). Using the anti-factor Xa (AFXa) channel, R-time demonstrated strong non-linear correlation with rivaroxaban and apixaban levels (rs = 0.92 and 0.84 respectively, p < 0.0001 for both). R-time revealed strong sensitivity and NPV in detecting low DOAC levels for the predefined concentrations. Conclusion: R-time measured by TEG®6s DOAC Specific cartridge has a strong correlation with concentrations of the most commonly used DOACs, with high sensitivity and NPV for detecting lower drug levels that are considered clinically relevant for patients in need of antidote, or prior to urgent surgery. Further studies to determine the relation of R-time to clinical outcomes are warranted.

scholarly journals Direct-Acting Oral Anticoagulants and Their Reversal Agents—An Update

Medicines ◽  
2019 ◽  
Vol 6 (4) ◽  
pp. 103 ◽  
Author(s):  
Stephanie Kustos ◽  
Pius Fasinu
Keyword(s):  
Oral Anticoagulants ◽  
Anticoagulation Therapy ◽  
Factor Xa ◽  
Rapid Onset ◽  
Thrombin Inhibitor ◽  
Reversal Agent ◽  
Onset Of Action ◽  
Reversal Agents ◽  
Direct Acting ◽  
Direct Acting Oral Anticoagulants

Background: Over the last ten years, a new class of drugs, known as the direct-acting oral anticoagulants (DOACs), have emerged at the forefront of anticoagulation therapy. Like the older generation anticoagulants, DOACs require specific reversal agents in cases of life-threatening bleeding or the need for high-risk surgery. Methods: Published literature was searched, and information extracted to provide an update on DOACS and their reversal agents. Results: The DOACs include the direct thrombin inhibitor—dabigatran, and the factor Xa inhibitors—rivaroxaban, apixaban, edoxaban, and betrixaban. These DOACs all have a rapid onset of action and each has a predictable therapeutic response requiring no monitoring, unlike the older anticoagulants, such as warfarin. Two reversal agents have been approved within the last five years: idarucizumab for the reversal of dabigatran, and andexanet alfa for the reversal of rivaroxaban and apixaban. Additionally, ciraparantag, a potential “universal” reversal agent, is currently under clinical development. Conclusions: A new generation of anticoagulants, the DOACs, and their reversal agents, are gaining prominence in clinical practice, having demonstrated superior efficacy and safety profiles. They are poised to replace traditional anticoagulants including warfarin.

scholarly journals Specific Point-of-Care Testing of Coagulation in Patients Treated with Dabigatran

2021 ◽  
Author(s):  
Florian Härtig ◽  
Ingvild Birschmann ◽  
Andreas Peter ◽  
Matthias Ebner ◽  
Charlotte Spencer ◽  
...  
Keyword(s):  
Point Of Care ◽  
Oral Anticoagulants ◽  
Direct Oral Anticoagulants ◽  
Rapid Assessment ◽  
Plasma Concentrations ◽  
High Sensitivity ◽  
Diagnostic Study ◽  
Blood Samples ◽  
Urgent Surgery ◽  
Coagulation Testing

Abstract Background and Purpose Accurate and rapid assessment of coagulation status is necessary to guide thrombolysis or reversal of anticoagulation in stroke patients, but commercially available point-of-care (POC) assays are not suited for coagulation testing in patients treated with direct oral anticoagulants (DOACs). We aimed to evaluate the direct thrombin monitoring (DTM) test card by Helena Laboratories (Texas, United States) for anti-IIa-specific POC coagulation testing, hypothesizing that its POC-ecarin clotting time (POC-ECT) accurately reflects dabigatran plasma concentrations. Methods A prospective single-center diagnostic study (ClinicalTrials.gov-identifier: NCT02825394) was conducted enrolling patients receiving a first dose of dabigatran and patients already on dabigatran treatment. Blood samples were collected before drug intake and 0.5, 1, 2, 8, and 12 hours after intake. POC-ECT was performed using whole blood (WB), citrated blood (CB), and citrated plasma (CP). Dabigatran plasma concentrations were determined by mass spectrometry. Results In total, 240 blood samples from 40 patients contained 0 to 275 ng/mL of dabigatran. POC-ECT with WB/CB/CP ranged from 20 to 186/184/316 seconds. Pearson's correlation coefficient showed a strong correlation between dabigatran concentrations and POC-ECT with WB/CB/CP (R2  = 0.78/0.90/0.92). Dabigatran concentrations >30 and >50 ng/mL (thresholds for thrombolysis, surgery, and reversal therapy according to clinical guidelines) were detected by POC-ECT with WB/CB/CP (>36/35/45 and >43/45/59 seconds) with 95/97/97 and 96/98/97% sensitivity, and 81/87/94 and 74/60/91% specificity. Conclusion This first study evaluating DOAC-specific POC coagulation testing revealed an excellent correlation of POC-ECT with actual dabigatran concentrations. Detecting clinically relevant dabigatran levels with high sensitivity/specificity, the DTM assay represents a suitable diagnostic tool in acute stroke, hemorrhage, and urgent surgery.

Reversal of DIRECT-ACTING Oral Anticoagulants in Urgent Surgery of the Proximal Aorta: case Series and Review of the literature

2019 ◽  
Vol 24 (38) ◽  
pp. 4534-4539 ◽  
Author(s):  
Eric Zimmermann ◽  
Fawzi Ameer ◽  
Berhane Worku ◽  
Dimitrios Avgerinos
Keyword(s):  
Oral Anticoagulants ◽  
Aortic Surgery ◽  
Management Strategies ◽  
Case Series ◽  
Published Data ◽  
Review Of Literature ◽  
Clotting Factors ◽  
Urgent Surgery ◽  
Direct Acting ◽  
Direct Acting Oral Anticoagulants

Introduction: Proximal aorta interventions impose significant bleeding risk. Patients on concomitant anticoagulation regimens compound the risk of bleeding in any surgery, but especially cardiothoracic interventions. The employment of direct-acting oral anticoagulants (DOAC), namely those that target clotting factors II or X, has expanded at a precipitous rate over the last decade. The emergence of their reversal agents has followed slowly, leaving clinicians with management dilemmas in urgent surgery. We discuss current reversal strategies based on the available published data and our experience with proximal aortic surgery in patients taking DOACs. Literature Search: We performed a review of literature and present three cases from our experience to offer insight into management strategies that have been historically successful. A review of literature was conducted via PubMed with the following search string: (NOAC or DOAC or TSOAC) and (aorta or aortic or (Stanford and type and a)). Case Presentation: We present three case presentations that illustrate the importance of DOAC identification and offer management strategies in mitigating associated bleeding risks in urgent or emergent surgeries. Conclusion: Treatment teams should be aware of the technical limitations of identifying and reversing DOACs. In view of the tendency toward publishing positive outcomes, more scientific rigor is required in the area of emergency DOAC reversal strategies.

scholarly journals Viscoelastometry for detecting oral anticoagulants

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Philipp Groene ◽  
Daniela Wagner ◽  
Tobias Kammerer ◽  
Lars Kellert ◽  
Andreas Giebl ◽  
...  
Keyword(s):  
Healthy Volunteers ◽  
Prospective Observational Study ◽  
Oral Anticoagulants ◽  
Plasma Concentrations ◽  
Factor Xa ◽  
Clotting Time ◽  
Emergency Situations ◽  
Tissue Plasminogen ◽  
The Impact

Abstract Background Determination of anticoagulant therapy is of pronounced interest in emergency situations. However, routine tests do not provide sufficient insight. This study was performed to investigate the impact of anticoagulants on the results of viscoelastometric assays using the ClotPro device. Methods This prospective, observational study was conducted in patients receiving dabigatran, factor Xa (FXa)-inhibitors, phenprocoumon, low molecular weight heparin (LMWH) or unfractionated heparin (UFH) (local ethics committee approval number: 17–525-4). Healthy volunteers served as controls. Viscoelastometric assays were performed, including the extrinsic test (EX-test), intrinsic test (IN-test) Russel’s viper venom test (RVV-test), ecarin test (ECA-test), and the tissue plasminogen activator test (TPA-test). Results 70 patients and 10 healthy volunteers were recruited. Clotting time in the EX-test (CTEX-test) was significantly prolonged versus controls by dabigatran, FXa inhibitors and phenprocoumon. CTIN-test was prolonged by dabigatran, FXa inhibitors and UFH. Dabigatran, FXa inhibitors and UFH significantly prolonged CTRVV-test in comparison with controls (median 200, 207 and 289 vs 63 s, respectively; all p < 0.0005). Only dabigatran elicited a significant increase in CTECA-test compared to controls (median 307 vs 73 s; p < 0.0001). CTECA-test correlated strongly with dabigatran plasma concentration (measured by anti-IIa activity; r = 0.9970; p < 0.0001) and provided 100% sensitivity and 100% specificity for detecting dabigatran. Plasma concentrations (anti-XA activity) of FXa inhibitors correlated with CTRVV-test (r = 0.7998; p < 0.0001), and CTRVV-test provided 83% sensitivity and 64% specificity for detecting FXa inhibitors. Conclusions In emergency situations, ClotPro viscoelastometric assessment of whole-blood samples may help towards determining the presence and type of anticoagulant class that a patient is taking. Trial registration German clinical trials database ID: DRKS00015302.

scholarly journals The Severity of Intracranial Hemorrhages Measured by Free Hemoglobin in the Brain Depends on the Anticoagulant Class: Experimental Data

2017 ◽  
Vol 2017 ◽  
pp. 1-4 ◽  
Author(s):  
Kyle M. Ware ◽  
Douglas L. Feinstein ◽  
Israel Rubinstein ◽  
Prudhvi Battula ◽  
Jose Otero ◽  
...  
Keyword(s):  
Vitamin K ◽  
Vitamin K Antagonists ◽  
Oral Anticoagulants ◽  
Direct Oral Anticoagulants ◽  
Factor Xa ◽  
Hemoglobin Concentration ◽  
Thrombin Inhibitor ◽  
Free Hemoglobin ◽  
Intracranial Hemorrhages ◽  
The Brain

Background and Purpose. Anticoagulant therapy is broadly used to prevent thromboembolic events. Intracranial hemorrhages are serious complications of anticoagulation, especially with warfarin. Direct oral anticoagulants reduce but do not eliminate the risk of intracranial hemorrhages. The aim of this study is to determine the degree of intracranial hemorrhage after application of anticoagulants without additional triggers. Methods. Rats were treated with different anticoagulant classes (vitamin K antagonists, heparin, direct thrombin inhibitor, and factor Xa inhibitor). Brain hemorrhages were assessed by the free hemoglobin concentration in the brain parenchyma. Results. Vitamin K antagonists (warfarin and brodifacoum) significantly increased free hemoglobin in the brain. Among direct oral anticoagulants, thrombin inhibitor dabigatran also significantly increased free hemoglobin in the brain, whereas treatment with factor Xa inhibitor rivaroxaban did not have significant effect on the free hemoglobin concentration. Conclusions. Our data indicates that the severity of brain hemorrhages depends on the anticoagulant class and it is more pronounced with vitamin K antagonists.

scholarly journals Chromogenic anti-Xa test: the ratio between heparin activity units and concentration of apixaban and rivaroxaban

2020 ◽  
pp. 96-104
Author(s):  
E. V. Titaeva ◽  
A. B. Dobrovolsky
Keyword(s):  
Oral Anticoagulants ◽  
Direct Oral Anticoagulants ◽  
Plasma Concentrations ◽  
Factor Xa ◽  
Activity Test ◽  
Formation Dynamics ◽  
Test Version ◽  
Heparin Activity ◽  
The Relationship ◽  
Thrombin Formation

Introduction. The direct oral anticoagulants (DOC) therapy does not require alaboratory control; however, it may be required to determine the anticoagulationlevel to choose a treatment strategy if alarge bleeding is developing or emergency surgery is needed.The objective of this experimental study was to investigate the relationship between the residual factor Xa (FXa) activity, anti-Xa activity units oflow molecular weight heparins (LMWH), and the apixaban and rivaroxaban plasma concentrations in a chromogenic anti-Xa assay.Material and methods. Concentrated DOC solutions were prepared by extracting apixaban and rivaroxaban from crushed tablets using methanol and dimethyl sulfoxide, respectively. The resulting solutions were added to the donor plasma pool until final inhibitor concentrations are achieved in the range from 10 to 100 ng/ml plasma. Anti-Xa activity was determined using an STA-compact analyser and the Liquid anti-Xa reagent kit, an analysis protocol, and calibrators designed to control the LMWH therapy. The effect on the thrombin formation dynamics was investigated using the thrombin generation test (TGT) and the PPR reagent as a trigger (final concentrations of tissue factor are 5 pM, and those of phospholipids are 4 μM). TGT curves were analysed using the Thrombinoscope program.Results. It was shown that in the anti-Xa activity test version designed to control the LMWH therapy, there is a high correlation (R2 > 0.98) between thelogarithm of the residual factor Xa activity and the content of apixaban and rivaroxaban in the range from 10 to 80 ng/ml. Rivaroxaban shows about 1.5 times more anti-Xa activity than apixaban at equal concentrations. It was also shown that apixaban and rivaroxaban at doses equal both in concentration and in anti-Xa activity differ in their effect on the thrombin formation dynamics and thrombin inactivation in the TGT.Conclusion. In the LMWH anti-Xa activity test version, the measured range of apixaban and rivaroxaban includes 30 ng/ml and 50 ng/ ml concentrations taken as “cut-off points” to determine the treatment tactics in emergency cases. However, thelack of certified DOC calibratorslimits the use of this test in clinical practice.

scholarly journals Therapeutic potential of apixaban at different stages of management of patients with pulmonary thromboembolism

2019 ◽  
pp. 8-15
Author(s):  
O. V. Averkov ◽  
V. I. Vechorko ◽  
O. A. Shapsigova
Keyword(s):  
Secondary Prevention ◽  
Anticoagulant Therapy ◽  
Therapeutic Potential ◽  
Pulmonary Thromboembolism ◽  
Oral Anticoagulants ◽  
Factor Xa ◽  
Evidence Base ◽  
Thrombin Inhibitor ◽  
Factor Xa Inhibitor ◽  
A Priority

The article discusses the issues of anticoagulant therapy in pulmonary thromboembolism. It clearly highlights the main advantages and the preferred use of direct selective oral anticoagulants represented by the thrombin inhibitor dabigatran and the factor Xa inhibitor group including apixaban, edoxaban and rivaroxaban. This article provides a thorough introduction of apixaban with an evidence base allowing to consider it a priority anticoagulant, which may be reasonably administered to the majority of patients with pulmonary thromboembolism from the first hours of the disease to many years of secondary prevention.

scholarly journals Update on Edoxaban for the Prevention and Treatment of Thromboembolism: Clinical Applications Based on Current Evidence

2015 ◽  
Vol 2015 ◽  
pp. 1-19 ◽  
Author(s):  
Ali Zalpour ◽  
Thein Hlaing Oo
Keyword(s):  
Vitamin K Antagonists ◽  
Dabigatran Etexilate ◽  
Oral Anticoagulants ◽  
Direct Oral Anticoagulants ◽  
Factor Xa ◽  
Coagulation Factors ◽  
Current Evidence ◽  
Thrombin Inhibitor ◽  
Prevention And Treatment ◽  
Financial Impacts

Vitamin K antagonists (VKA) and heparins have been utilized for the prevention and treatment of thromboembolism (arterial and venous) for decades. Targeting and inhibiting specific coagulation factors have led to new discoveries in the pharmacotherapy of thromboembolism management. These targeted anticoagulants are known as direct oral anticoagulants (DOACs). Two pharmacologically distinct classes of targeted agents are dabigatran etexilate (Direct Thrombin Inhibitor (DTI)) and rivaroxaban, apixaban, and edoxaban (direct oral factor Xa inhibitors (OFXaIs)). Emerging evidence from the clinical trials has shown that DOACs are noninferior to VKA or low-molecular-weight heparins in the prevention and treatment of thromboembolism. This review examines the role of edoxaban, a recently approved OFXaI, in the prevention and treatment of thromboembolism based on the available published literature. The management of edoxaban in the perioperative setting, reversibility in bleeding cases, its role in cancer patients, the relevance of drug-drug interactions, patient satisfaction, financial impacts, and patient education will be discussed.

scholarly journals The Reversal of Bleeding Caused by New Oral Anticoagulants (NOACs): A Systematic Review and Meta-Analysis

2018 ◽  
Vol 24 (9_suppl) ◽  
pp. 117S-126S ◽  
Author(s):  
Sariya Udayachalerm ◽  
Sasivimol Rattanasiri ◽  
Teeranan Angkananard ◽  
John Attia ◽  
Nakarin Sansanayudh ◽  
...  
Keyword(s):  
Case Reports ◽  
Meta Analysis ◽  
Oral Anticoagulants ◽  
Factor Xa ◽  
New Oral Anticoagulants ◽  
Thrombin Inhibitor ◽  
Aggregated Data ◽  
Reversal Agents ◽  
Death Studies ◽  
Risk Of Death

New oral anticoagulants (NOACs; ie, direct thrombin inhibitor [DTI] and factor Xa [FXa] inhibitors) were used as alternatives to warfarin. Specific antidotes (idarucizumab for dabigatran and andexanet alfa for FXa inhibitors) and hemostatic reversal agents were used for lowering bleeding, but their efficacies were still uncertain. The objectives of this study were to estimate and compare the efficacy of NOAC antidotes on bleeding reversal and death. Studies were identified from MEDLINE and Scopus databases until May 2018. Case reports/series and cohorts were selected if they assessed reversal or death rates. Data were independently extracted by 2 reviewers. Individual patient data and aggregated data of outcomes were extracted from case reports/series and cohorts. Binary regression was used to estimate outcome rates, risk ratio (RR) along with 95% confidence interval (CI). Interventions were NOACs and reversal agents (ie, DTI-specific, DTI-standard, FXa-specific, and FXa-standard). Among 220 patients of 93 case reports/series, reversal rates were 95.9%, 77.6%, and 71.5% for DTI-specific, FXa-standard, and DTI-standard. Pooled RRs for DTI-specific and FXa-standard versus DTI-standard, respectively, were 1.34 (CI: 1.13-1.60) and 1.09 (CI: 0.84-1.40). Death rate was 0.18 (CI: 0.06-0.57) times lower in DTI-specific versus DTI-standard. For pooling 10 subcohorts, pooled RRs were 1.08 (CI: 1.00-1.16), 1.29 (CI: 1.20-1.39), and 1.13 (CI: 1.01-1.25) for DTI-specific, FXa-specific, and FXa-standard versus DTI-standard. In conclusion, specific reversal agents might be useful for reversal of bleeding and lowering the risk of death than standard reversal agents. Our findings were based on case reports/series and selected cohorts, further comparative studies are thus needed.

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