Thrombin generation test in patients under anticoagulant therapy with vitamin k antagonists

2009 ◽  
Vol 101 (03) ◽  
pp. 594-595 ◽  
Author(s):  
Isabel Brocal ◽  
Javier Lucas ◽  
José Verdú ◽  
Fabián Tarín ◽  
Pascual Marco
Keyword(s):  
Anticoagulant Therapy ◽  
Vitamin K ◽  
Thrombin Generation ◽  
Vitamin K Antagonists ◽  
Generation Test

Differential inhibition of thrombin generation by vitamin K antagonists alone and associated with low-molecular-weight heparin

2009 ◽  
Vol 102 (07) ◽  
pp. 42-48 ◽  
Author(s):  
Grigoris T. Gerotziafas ◽  
Charlotte Dupont ◽  
Alex C. Spyropoulos ◽  
Mohamed Hatmi ◽  
Meyer M. Samama ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Vitamin K ◽  
Low Molecular Weight Heparin ◽  
Thrombin Generation ◽  
Vitamin K Antagonists ◽  
Low Molecular Weight ◽  
Plasma Samples ◽  
Thrombin Generation Assay ◽  
International Normalised Ratio ◽  
Inhibition Of Thrombin

SummaryVitamin K antagonists (VKA) treatment starts with co-administration of low-molecular-weight heparin (LMWH). The anticoagulation induced by the two drugs is still not well determined. In the present study we used thrombin generation assay to evaluate the hypo-coagulation induced by treatment with VKA and by the combination of VKA with LMWH. Tissue factor triggered thrombin generation in platelet-poor plasma was assessed in samples from 15 healthy volunteers, 97 samples from patients treated with VKA and 41 samples from patients receiving enoxaparin and VKA. Patients were classified according to international normalised ratio (INR) level (<2, 2–3 and >3).In plasma samples from patients treated with VKA having INR 2–3 the inhibition of thrombin generation reached 50% compared to controls. In samples with INR>3 this inhibition was 80%. In samples from patients receiving both LMWH and VKA, thrombin generation was significantly decreased compared to the controls and VKA group. In samples with an INR 2–3 obtained from patients treated with LMWH and VKA, the inhibition of thrombin generation was similar to that observed in samples with an INR>3 obtained from VKA treated patients. Thrombin generation assay is sensitive to detect the global the anticoagulant effect produced by the association of LMWH and VKA. For equal INR dual anticoagulant treatment induces significantly more profound inhibition of thrombin generation compared to treatment with VKA alone. The clinical relevance of this observation merits to be studied in prospective studies in patients with defined indications of anticoagulant therapy.

Suspension of Vitamin K Antagonists Is Not Required for Cataract Surgery: A Prospective Study in a Cohort of 135 Consecutive Patients on Long-Term Anticoagulant Therapy.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 882-882
Author(s):  
Berardino Pollio ◽  
Giuseppe A. Demarie ◽  
Patrizia Ocello ◽  
Grazia Delios ◽  
Marco Tucciarone ◽  
...  
Keyword(s):  
Cataract Surgery ◽  
Anticoagulant Therapy ◽  
Vitamin K ◽  
Oral Anticoagulant ◽  
Oral Anticoagulant Therapy ◽  
Vitamin K Antagonists ◽  
Management Service ◽  
Corneal Incision ◽  
Standardized Protocol

Abstract The perioperative management of oral anticoagulant therapy (OAT) often arouses controversy between surgeons and internists. In geriatric patients, cataract surgery for those who are taking vitamin K antagonists is a common clinical procedure. Phacoemulsification requires a 3 mm incision involving a tissue devoid of blood vessels. This study reports the experience of an Italian Anticoagulation Management Service (AMS) with 135 anticoagulated patients on long-term anticoagulant therapy who underwent phacoemulsification performed by the same ophthalmologist team from January 2001 to December 2005. The patients received either topical (30%) or peribulbar (70%) anaesthesia. Data were collected by physicians with specialized software, but the dosage of oral anticoagulant was manual. Two oral vitamin K antagonisists are available in Italy: acenocumarol and warfarin. We prepared all patients in accordance with the following standardized protocol : the scheduled dose was always omitted the day before surgery an INR measurement was provided 3–5 days before the invasive procedure; if the patient’s INR was below 3, we simply omitted the scheduled dose of the day before cataract surgery if the patient’s INR was above 3, we withheld two or more scheduled doses to allow the INR to fall to 2.5 or less 1 hour before cataract surgery, INR was measured if the patient’s INR was below 2.5, phacoemulsification was performed Results: This standardized procedural protocol allowed the surgeon to carry out phacoemulsification with INR always below 2.5. We observed only one peribulbar bleeding (0.7%) during peribulbar anaesthesia before the corneal incision was made. No thromboembolic complications were registered during three months of follow up. We compared our results with the data of an earlier cohort of 7014 conventional patients who underwent this eye surgery in the same ophthalmologic institute. We did not observe statistical differences between the two groups with regard to hemorragic complications. Conclusions: The risk of thromboembolism when antithrombotic therapy is interrupted is a well-grounded concern, particularly for patients with mechanical heart valves. Low molecular weight heparin bridging is a valid but more complicated alternative. Our study demonstrates the feasibility and safety of this simple standardized protocol which avoids OAT interruption. Therefore, we conclude that in patients receiving OAT, it is not necessary for the anticoagulant effect to wear off before cataract surgery is performed.

scholarly journals Vitamin K Concentration and Cognitive Status in Elderly Patients on Anticoagulant Therapy: A Pilot Study

2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Ludovico Alisi ◽  
Clodomiro Cafolla ◽  
Alessandra Gentili ◽  
Sara Tartaglione ◽  
Roberta Curini ◽  
...  
Keyword(s):  
Elderly Patients ◽  
Anticoagulant Therapy ◽  
Vitamin K ◽  
Cognitive Functions ◽  
Oral Anticoagulant Therapy ◽  
Vitamin K Antagonists ◽  
Positive Association ◽  
Cognitive Status ◽  
Vitamin K1 ◽  
The Relationship

Objectives. Recent studies have suggested that vitamin K may exert significant effects on the central nervous system. The present study investigates the relationship between vitamin K plasmatic levels and cognitive functions in elderly patients on oral anticoagulant therapy (OAT). Design. At the Thrombosis Centre of Haematology, “Sapienza” University of Rome, 85 patients on OAT, aged between 75 and 92, were randomly enrolled in the study. Patients were on OAT with vitamin K antagonists (VKAs). Vitamin K1 concentrations were determined using standardized High-Performance Liquid Chromatography (HPLC). Cognitive functions were assessed using the Milan Overall Dementia Assessment (MODA). Results. MODA scores are positively correlated to vitamin K1 concentration. Patients with vitamin K1 below 0.100 μg/L and between 0.100 and 0.400 μg/L showed a mean MODA score of 79 ± 5 and 82 ± 3, respectively. Patients with vitamin K1 above 0.400 μg/L had a significantly greater MODA score (89 ± 1). After binning the data into bicentiles, MODA scores are shown to be linearly dependent on vitamin K1 concentrations (p<0.001). Even long-term OAT (>10 years) does not affect MODA scores. Education seems to exert a greater role on the cognitive status in comparison with aging. Conclusions. The study shows a positive association between vitamin K1 concentration and cognitive status in elderly patients (≥75 years) on OAT. The relationship between vitamin K1 concentration and MODA scores is described by a linear model. Cognitive status is not influenced by the duration of OAT but by the years of education.

scholarly journals Az edoxabán véralvadásgátló hatásossága és biztonságossága nonvalvuláris pitvarfibrillációban

2018 ◽  
Vol 159 (12) ◽  
pp. 466-469
Author(s):  
Andrea Szegedi ◽  
Zoltán Csanádi
Keyword(s):  
Atrial Fibrillation ◽  
Anticoagulant Therapy ◽  
Vitamin K ◽  
Oral Anticoagulant ◽  
Randomized Trials ◽  
Vitamin K Antagonists ◽  
Thromboembolic Events ◽  
Direct Oral Anticoagulant ◽  
Anticoagulant Drugs

Abstract: The significantly increased incidence of stroke and systemic embolisation caused by atrial fibrillation can be prevented by adequately adjusted anticoagulant therapy. Vitamin K antagonists effectively decrease the risk of thromboembolic events but this effect is influenced by many factors. The development of the new direct oral anticoagulant drugs (DOAC) in the last few years provided new opportunities for us to choose the suitable anticoagulant therapy. According to the results of the ENGAGE AF–TIMI 48 and ENSURE-AF multicenter, randomized trials, edoxaban, the recently introduced DOAC is equally effective as the traditional coumarin therapy, nevertheless, it ensures more tolerable anticoagulation for patients suffering from non-valvular atrial fibrillation. Orv Hetil. 2018; 159(12): 466–469.

scholarly journals Incidence of complications of antithrombotic treatment in patients with atrial fibrillation

2013 ◽  
Vol 66 (11-12) ◽  
pp. 470-475
Author(s):  
Sladjana Novakovic-Anucin ◽  
Sanja Gnip ◽  
Visnja Canak ◽  
Pavica Radovic ◽  
Jelena Kovacev ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Ischemic Stroke ◽  
Anticoagulant Therapy ◽  
Vitamin K ◽  
Oral Anticoagulant Therapy ◽  
Vitamin K Antagonists ◽  
Combined Treatment ◽  
Thromboembolic Complications ◽  
Antithrombotic Treatment ◽  
Hemorrhagic Complications

Introduction. Atrial fibrillation increases the risk of ischemic stroke five fold, while the application of long-term anticoagulant therapy is associated with the occurrence of hemorrhagic complications. The aim of our study was to evaluate the incidence of thrombotic and hemorrhagic complications in patients with atrial fibrillation during antithrombotic treatment. Material and Methods. The study included 504 patients that were administered the primary (n=345) or secondary thromboprophylaxis after ischemic stroke (n=159), by applying vitamin K antagonists, or the combination of vitamin K antagonists and low-dose aspirin. The patients were followed for five months in the period of 24 years from 1988 to 2012, the total number of patient?s years being 1884, at the Clinical Center of Vojvodina. Thromboembolic and hemorrhagic complications were registered during regular check-up examinations. Results and Discussion. Our results indicate the low incidence of thromboembolic complications (0.01 patient per a year), with a lower incidence in the vitamin K antagonists group than in the group with the combination of vitamin K antagonists and aspirin (0.008 patient per a year versus 0.01 patient per a year). The incidence of hemorrhagic complications was higher in the group with the combined treatment compared to the group treated with vitamin K antagonists (0.1 patient per a year versus 0.06 patient per a year). The frequency of major bleeding was as low as 0.01 patient per a year and more frequent in the group with combined treatment (0.03 patient per a year). Conclusion. The overall incidence of complications in the study group was 0.08 patient per a year. The combined antithrombotic treatment increases the risk of hemorrhagic complications and affects the severity of bleeding. Oral anticoagulant therapy is more efficient in the prevention of ischemic stroke and thromboembolic complications in patients with atrial fibrillation.

scholarly journals Anticoagulation therapy in the elderly with non-valvular atrial fibrillation: a double-edged sword

2017 ◽  
Vol 3 (2) ◽  
Author(s):  
Francesco Vetta ◽  
Gabriella Locorotondo ◽  
Giampaolo Vetta
Keyword(s):  
Atrial Fibrillation ◽  
Elderly Patients ◽  
Anticoagulant Therapy ◽  
Vitamin K ◽  
Vitamin K Antagonists ◽  
Oral Anticoagulants ◽  
Anticoagulation Therapy ◽  
Treatment Strategies ◽  
The Elderly ◽  
Hemorrhagic Events

Prevalence of non-valvular atrial fibrillation is increasing over time. Particularly in elderly population, treatment strategies to reduce the rate of stroke are challenging and still represent an unsolved cultural question. Indeed, the risk of thromboembolism increases in the elderly in parallel with the risk of bleeding. The frequent coexistence of several morbidities, frailty syndrome, polypharmacy, chronic kidney disease and dementia strengthens the perception that risk-benefit ratio of anticoagulant therapy could be unfavorable, and explains why such treatment is underused in the elderly. Recently, the introduction of non-vitamin K oral anticoagulants (NOACs) has allowed us to overcome the large number of limitations imposed by the use of vitamin K antagonists. In this manuscript, the benefits of individual NOACs in comparison with warfarin in elderly patients are reviewed. Targeted studies on complex elderly patients are needed to test usefulness of a geriatric comprehensive assessment, besides the scores addressing risk of thromboembolic and hemorrhagic events. In the meantime, it is mandatory that use of anticoagulant therapy in most elderly people, currently excluded from randomized controlled trials, is prudent and responsible.

Sign in / Sign up

Export Citation Format

Share Document