Fibrinography and thrombography (thrombodynamics-4D) in atrial fibrillation assessment of direct oral anticoagulants in geriatrics patients aged 80 years and older receiving direct oral anticoagulant therapy.

Background: Scarce data are available on pharmacodynamic (PD) variability in very elderly patients receiving direct oral anticoagulants (DOACs) for atrial fibrillation (AF). Thrombodynamics-4D (TD-4D), which simultaneously assesses fibrin clot formation and thrombin generation, has not yet been tested in patients on rivaroxaban, apixaban, or dabigatran.

Objectives: To (i) evaluate TD-4D's ability to assess DOAC effect added to normal plasma; (ii) assess DOAC PD in very elderly patients with AF along with DOAC concentrations; (iii) identify factors associated with interindividual variability of DOAC PD at peak and trough levels.

Effect of heparins, direct oral anticoagulants, and factor XII/factor XI inhibitors on catheter-initiated thrombin generation in platelet-rich plasma: an in vitro study.

Background: Invasive endovascular procedures often require anticoagulation to prevent device-associated thrombosis. High doses of unfractionated heparin (UFH) are the gold standard. The efficacy of factor (F)XII(a) and FXI(a) inhibitors remains unexplored.

Thromboembolism in transplant-ineligible multiple myeloma patients on triplet/quadruplet therapy: a post hoc analysis of BENEFIT trial.

Background: Venous thromboembolism (VTE) events remain a major concern for patients with newly diagnosed multiple myeloma (nMM) undergoing therapy.

Objectives: Evaluate the incidence and risk factors for VTE.

Methods: Post hoc analysis of the randomized phase 3 BENEFIT trial (NCT04751877) evaluating 257 patients aged 65 to 79 years with transplant-ineligible nMM who received isatuximab/bortezomib/lenalidomide/dexamethasone or isatuximab/lenalidomide/dexamethasone.

Management of bleeding and invasive procedures in patients treated with anti-factor XI(a) anticoagulants: proposals from the French Working Group on Perioperative Haemostasis and French Society of Thrombosis and Haemostasis.

Background: Several anti-FXI(a) agents with distinct mechanisms of action and pharmacological properties are currently under clinical development. While these anticoagulants are not yet available, there is a need to address bleeding risk management for patients already enrolled in phase III trials. These patients may face elective or unplanned invasive procedures and bleeding events in anticipation of marketing authorization.

Anticoagulant drugs targeting factor XI/XIa and coagulation tests: we urgently need reliable pharmacodynamic data.

Antifactor (F)XI/FXIa anticoagulants under development include antisense oligonucleotides, monoclonal antibodies, and small molecules. They do not require routine monitoring, but knowledge of their impact on coagulation tests is essential in view of their expected widespread use. A concentration-dependent prolongation of activated partial thromboplastin time has been shown but varies according to reagents, and the lack of comprehensive data makes interpretation of this test difficult.

Results of an international survey on the management of therapeutic intensity unfractionated heparin: communication from the SSCs of the ISTH.

Background: Unfractionated heparin (UFH) remains the anticoagulant of choice in critically ill patients. However, its laboratory monitoring and clinical management are particularly challenging.

Objectives: Our objective was to describe current practices and variations among centers of the ISTH.

Guidance-Based Appropriateness of Hemostasis Testing in the Acute Setting.

In this review, we aim to highlight the extent of inappropriate hemostasis testing and provide practical guidance on how to prevent it. We will focus on the acute setting, including but not limited to the emergency department and intensive care unit. To this end, we will first discuss the significance of inappropriateness, in the general context of laboratory medicine.

Prevention of perioperative venous thromboembolism: 2024 guidelines from the French Working Group on Perioperative Haemostasis (GIHP) developed in collaboration with the French Society of Anaesthesia and Intensive Care Medicine (SFAR), the French Society of Thrombosis and Haemostasis (SFTH) and the French Society of Vascular Medicine (SFMV) and endorsed by the French Society of Digestive Surgery (SFCD), the French Society of Pharmacology and Therapeutics (SFPT) and INNOVTE (Investigation Network On Venous ThromboEmbolism) network.

Background: Any surgical procedure carries a risk for venous thromboembolism (VTE), albeit variable. Improvements in medical and surgical practices and the shortening of care pathways due to the development of day surgery and enhanced recovery after surgery, have reduced the perioperative risk for VTE.

Objective: A collaborative working group of experts in perioperative haemostasis updated in 2024 the recommendations for the Prevention of perioperative venous thromboembolism published in 2011.

Management of Therapeutic-intensity Unfractionated Heparin: A Narrative Review on Critical Points.

Nowadays, unfractionated heparin (UFH) use is limited to selected patient groups at high risk of both bleeding and thrombosis (patients in cardiac surgery, in intensive care unit, and patients with severe renal impairment), rendering its management extremely challenging, with many unresolved questions despite decades of use. In this narrative review, we revisit the fundamental concepts of therapeutic anticoagulation with UFH and address five key points, summarizing controversies underlying the use of UFH and discussing the few recent advances in the field: (1) laboratory tests for UFH monitoring have significant limitations; (2) therapeutic ranges are not well grounded; (3) the actual influence of antithrombin levels on UFH's anticoagulant activity is not well established; (4) the concept of UFH resistance lacks supporting data; (5) scarce data are available on UFH use beyond acute venous thromboembolism. We therefore identified key issues to be appropriately addressed in future clinical research: (1) while anti-Xa assays are often considered as the preferred option, we call for a vigorous action to improve understanding of the differences between types of anti-Xa assays and to solve the issue of the usefulness of added dextran; (2) therapeutic ranges for UFH, which were defined decades ago using reagents no longer available, have not been properly validated and need to be confirmed or reestablished; (3) UFH dose adjustment nomograms require full validation.

Is lupus anticoagulant testing with dilute Russell's viper venom clotting times reliable in the presence of inflammation?

Background: Testing for lupus anticoagulant (LA) is not recommended in case of inflammation as C-reactive protein (CRP) can interfere with the phospholipids present in the activated partial thromboplastin time test used to detect an LA. However, the potential interference of an acute phase protein (ie, CRP) in LA testing using the dilute Russell's viper venom (DRVV) test is poorly studied.

Objectives: To study the effect of inflammation, as evidenced by increased CRP levels, on DRVV tests.

Mepacrine Flow Cytometry Assay for the Diagnosis of Platelet δ-granule Defects: Literature Review on Methods-Towards a Shared Detailed Protocol.

Accurate assessment of platelet secretion is essential for the diagnosis of inherited or acquired platelet function disorders and more specifically in identifying δ-storage pool disease. Mepacrine, a fluorescent dye, specifically accumulates in platelet δ-granules. The mepacrine flow cytometry (mepacrine FCM) assay has been used for more than half a century in the clinical laboratory as a diagnostic tool for platelet δ-granule disorders.

Thrombin Generation Assay in Antiphospholipid Antibodies Positive Subjects as a Personalized Thrombotic Risk Assessment: State of the Art and Perspectives.

Purpose Of The Review: Thrombotic risk assessment in antiphospholipid positive (aPL +) subjects is a major challenge, and the study of in vitro thrombin generation (thrombin generation assays (TGA)) could provide useful information. Activated protein C (APC) sensitivity is involved in thrombotic events in antiphospholipid syndrome patients. We summarized methods used to assess APC sensitivity with TGA and evaluated the prognostic role of APC resistance through literature search.

Prothrombin conversion and thrombin decay in patients with cirrhosis-role of prothrombin and antithrombin deficiencies.

Background: Thrombin generation (TG) in the presence of thrombomodulin (TG-TM) in the plasma of patients with cirrhosis (PWC) is tilted toward a hypercoagulable phenotype. Low protein C and elevated factor VIII levels play a role, but other determinants, such as the prothrombin/antithrombin pair, must also be studied.

Objectives: The objectives were (i) to quantitatively assess the subprocesses (prothrombin conversion and thrombin decay) and (ii) to understand the underlying mechanism by studying TG dynamics after prothrombin and antithrombin plasma level correction in PWC.

Laboratory Monitoring of Heparin Anticoagulation in Hemodialysis: Rationale and Strategies.

Unfractionated heparin (UFH) and low-molecular-weight heparins (LMWHs) are commonly used to prevent clotting of the hemodialysis extracorporeal circuit and optimize hemodialysis adequacy. There is no consensus on the optimal dosing for UFH and LMWHs during hemodialysis. In clinical practice, semiquantitative clotting scoring of the dialyzer and venous chamber may help to guide UFH and LMWH dose adjustment.

Antithrombin Levels and Heparin Responsiveness during Venoarterial Extracorporeal Membrane Oxygenation: A Prospective Single-center Cohort Study.

Background: Unfractionated heparin, administered during venoarterial extracorporeal membrane oxygenation to prevent thromboembolic events, largely depends on plasma antithrombin for its antithrombotic effects. Decreased heparin responsiveness seems frequent on extracorporeal membrane oxygenation; however, its association with acquired antithrombin deficiency is poorly understood. The objective of this study was to describe longitudinal changes in plasma antithrombin levels during extracorporeal membrane oxygenation support and evaluate the association between antithrombin levels and heparin responsiveness.

Reassessment of dextran sulfate in anti-Xa assay for unfractionated heparin laboratory monitoring.

Background: Anti-Xa assays are used for unfractionated heparin (UFH) monitoring. Dextran sulfate (DS) is used in some assays to overcome the artifactual preanalytical release of platelet factor 4. However, the practical implications of this test modification have not been studied extensively.

Venous thromboembolism prophylaxis and multiple myeloma patients in real-life: Results of a large survey and clinical guidance recommendations from the IFM group.

Venous thromboembolism (VTE) remains a critical issue in the management of patients with multiple myeloma (MM), particularly when immunomodulatory drugs (IMiDs) combined with dexamethasone therapy are being prescribed as first-line and relapse therapy. One possible explanation for the persistent high rates of VTE, is the use of inappropriate thromboprophylaxis strategies for patients starting antimyeloma treatment. To tackle the issue, the Intergroupe francophone du myélome (IFM) offered convenient guidance for VTE thromboprophylaxis in MM patients initiating systemic therapy.