Relationship between thrombin generation and international normalized ratio in patients receiving oral vitamin K antagonist therapy

Altman, Raúl; Scazziota, Alejandra; Herrera, Lourdes; González, C.

doi:10.1111/j.1538-7836.2007.02606.x

Cited by 15 publications

(15 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The ETP ratio for therapeutic INR observed in our study (0.17) is at the lower limit of reported ETP ratios. The ETP ratio for sub‐therapeutic INR in the present study (0.38) was also lower than in previous studies reporting ETP ratios of 0.45–0.60 . This may be because of the use of different TG testing protocols.…”

Section: Discussioncontrasting

confidence: 85%

“…When we express our threshold of 400 n m *min as a ratio of the median ETP value obtained in healthy controls, the ETP ratio of our threshold will be 0.45. This is near the upper limit of reported ETP ratios of 0.20–0.40 in patients with therapeutic INR , thus suggesting that this threshold indeed covers the therapeutic range of INR. The ETP ratio for therapeutic INR observed in our study (0.17) is at the lower limit of reported ETP ratios.…”

Section: Discussionsupporting

confidence: 49%

See 1 more Smart Citation

Comparing thrombin generation in patients with hemophilia A and patients on vitamin K antagonists

Koning

Fischer

Laat

et al. 2017

Journal of Thrombosis and Haemostasis

View full text Add to dashboard Cite

Essentials It is unknown if hemophilia patients with atrial fibrillation need anticoagulation. Endogenous thrombin potentials (ETP) in hemophilia patients and patients on coumarins were compared. Severe hemophilia patients had comparable ETP to therapeutic international normalized ratio (INR). In non-severe hemophilia, 33% had higher ETP than therapeutic INR and may need anticoagulation. Click to hear Dr Negrier's perspective on global assays for assessing coagulation SUMMARY: Background It is unknown whether patients with hemophilia A with atrial fibrillation require treatment with vitamin K antagonists (VKAs) to the same extent as the normal population. Objective To compare hemostatic potential in hemophilia patients and patients on VKAs using thrombin generation (TG). Methods In this cross-sectional study, TG, initiated with 1pM tissue factor, was measured in 133 patients with severe (FVIII < 1%, n = 15) and non-severe (FVIII 1-50%, n = 118) hemophilia A, 97 patients on a VKA with an international normalized ratio (INR) ≥ 1.5 and healthy controls. Endogenous thrombin potential (ETP) (nm*min) was compared according to FVIII level (< 1%, 1-19% and 20-50%) with healthy controls and patients with sub-therapeutic INR (1.5-1.9) and therapeutic INR (≥ 2.0). Medians and interquartile ranges (IQRs) were calculated. Results Compared with healthy controls (898 [IQR 803-1004]), both hemophilia patients and patients on VKAs had lower median ETPs at 304 (196-449) and 176 (100-250), respectively. ETP was quite similar in severe hemophilia patients (185 [116-307]) and patients with a therapeutic INR (156 [90-225]). Compared with patients with therapeutic INR, ETP in patients with FVIII 1-19% and patients with FVIII 20-50% was higher at 296 (203-430) and 397 (219-632), respectively. All patients with therapeutic INR had an ETP < 400. Considering this threshold, 93% of severe hemophilia patients, 70% of patients with FVIII 1-19% and 52% of patients with FVIII 20-50% had an ETP < 400. Conclusion In severe hemophilia patients, TG was comparable to that in patients with a therapeutic INR. In one-third of non-severe hemophilia patients, TG was higher. These results suggest that anticoagulation therapy should be considered in a substantial proportion of non-severe hemophilia patients.

show abstract

Section: Discussioncontrasting

confidence: 85%

Section: Discussionsupporting

confidence: 49%

Comparing thrombin generation in patients with hemophilia A and patients on vitamin K antagonists

Koning

Fischer

Laat

et al. 2017

Journal of Thrombosis and Haemostasis

View full text Add to dashboard Cite

show abstract

“…There is a weak relationship between the thrombin potential and INR, but this is not linear and is affected by type of thromboplastin and its international sensitivity index [6,7]. The thrombin generation assay is also affected by the concentration and type of tissue factor used and shows a nonlinear relationship with clotting factors except for prothrombin, which is linear.…”

Section: Discussionmentioning

confidence: 98%

Anticoagulation of a patient with hypertrophic cardiomyopathy and factor VII deficiency

Davidson

Turner

Tillyer

2010

Blood Coagulation &Amp; Fibrinolysis

View full text Add to dashboard Cite

A 50-year-old male patient with hypertrophic cardiomyopathy and atrial fibrillation was anticoagulated, with warfarin following insertion of a cardioverter defibrillator. He became markedly over anticoagulated after standard moderate induction doses of warfarin. His baseline prothrombin time was prolonged and further investigation showed the patient to have a mild factor VII deficiency. He was restarted on low-dose warfarin and successfully stabilized with a target international normalized ratio (INR) of 3.0 (range 2.5-3.5). We used the data from factor VII levels and thrombin generation studies before and after anticoagulation to control dosage and to decide on a suitable therapeutic range for the INR. Molecular studies showed him to have two separate mutations in the factor VII gene. This report highlights the importance of noting the baseline prothrombin time before initiating oral anticoagulation and describes how well tolerated anticoagulation can be achieved in a patient with congenital factor VII deficiency.

show abstract

“…Given the wide variation in platelet function and non-vitamin K dependent factor levels between individuals, it is possible that a more global assay would better assess the bleeding risk in a given patient on oral anticoagulation. One such assay might be thrombin generation (TG), [25] an old test which resurfaced in the last few years thanks to the application of modern automated laboratory medicine technology to what used to be a painstaking manual process [26][27][28][29][30].…”

Section: Discussionmentioning

confidence: 99%

Determinants of intracranial hemorrhage incidence in patients on oral anticoagulation followed at the Lahey clinic

Mantha

Pianka

Tsapatsaris

2011

J Thromb Thrombolysis

View full text Add to dashboard Cite

Oral anticoagulation with warfarin is widely used to treat venous and arterial thromboembolic disease (Ansell et al. Chest 133(6 suppl):160S-198S, 2008). Its administration is associated with a risk of intracranial hemorrhage (ICH), a devastating complication which usually results in death or severe disability (Fang et al. Am J Med,120(8):700-705, 2007; Rosand et al. Arch Intern Med, 164(8):880-884, 2004). The international normalized ratio (INR) is one of the factors which can help determine the risk of ICH in a given individual (Singer et al. Circ Cardiovasc Qual Outcomes, 2(4):297-304, 2009). Using the DoseResponse(®) patient database at our institution, we carried a retrospective nested matched case-control study to identify patient characteristics associated with the occurrence of ICH. The database was queried for the years 2004-2009. Each case was matched by month to four control patients having a routine INR determination for the monitoring of chronic anticoagulation. The following characteristics were captured: bleeding type, INR, age, sex, blood pressure, hemoglobin, creatinine, presence or history of pertinent comorbid conditions, intake of antiplatelet agents (aspirin or thienopyridine) and indication for anticoagulation. The relationship between those risk factors and the odds ratio of ICH was determined with conditional logistic regression. Fifty cases of ICH were retrieved. When correcting for pertinent variables, the odds ratio of ICH increased significantly for higher INR values, with a quadratic relationship noted in the model. Increasing mean blood pressure seemed to be associated with a higher risk of ICH, also in an exponential manner. Rising hemoglobin values on the other hand seemed to have a protective effect against such events. About 50% of cases of ICH occurred in or below the therapeutic INR range. The intake of antiplatelet agent was found to be associated with ICH in univariate analysis only. The INR is an important predictor for the incidence of ICH, but in this study an elevated measurement was found in only half of cases. Mean blood pressure appears to be another important determinant of the risk of ICH in the anticoagulated patient population.

show abstract

Relationship between thrombin generation and international normalized ratio in patients receiving oral vitamin K antagonist therapy

Cited by 15 publications

References 9 publications

Comparing thrombin generation in patients with hemophilia A and patients on vitamin K antagonists

Comparing thrombin generation in patients with hemophilia A and patients on vitamin K antagonists

Anticoagulation of a patient with hypertrophic cardiomyopathy and factor VII deficiency

Determinants of intracranial hemorrhage incidence in patients on oral anticoagulation followed at the Lahey clinic

Contact Info

Product

Resources

About