Detection of shortened activated partial thromboplastin times: An evaluation of different commercial reagents

Boekel, Edwin ten; Böck, Martine; Vrielink, Gert-Jan; Liem, Rsb; Hendriks, Henriët; Kieviet, Wim de

doi:10.1016/j.thromres.2007.05.006

Cited by 39 publications

(30 citation statements)

References 21 publications

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“…In previous studies, several procoagulant markers have been found to be elevated in individuals with short APTTs [2][3][4][5][6][7][8][9][10], but these may not fully explain the thrombotic risk in these individuals, and thus, the presence of additional markers or risk factors can be hypothesized. In the current study, we prospectively assessed the profile of 113-test samples that yielded short APTTs in comparison with a similar number of age and sex-matched samples yielding normal APTTs.…”

Section: Discussionmentioning

confidence: 99%

“…Short APTTs have traditionally been considered an artefact of problematic blood collections giving rise to in-vitro activation events; however, recent evidence suggests that short APTTs might instead reflect in-vivo events that might be associated with hypercoagulability. Thus, patients with short APTTs have increased thrombin generation, elevated FVIII and thrombin-antithrombin complex, and are at increased risk for thromboembolism, mainly venous thromboses [1][2][3][4][5][6]. Furthermore, hypercoagulability detected by a shortened APTT appears to be significantly associated with the risk of venous thromboembolism independently of other variables such as blood group and the presence of inherited thrombophilia (reviewed in [1]).…”

Section: Introductionmentioning

confidence: 99%

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A laboratory evaluation into the short activated partial thromboplastin time

Mina¹,

Favaloro

Mohammed

et al. 2010

Blood Coagulation &Amp; Fibrinolysis

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Although short activated partial thromboplastin times (APTTs) are generally considered to be laboratory artefacts of problematic blood collections, there is mounting evidence that in some cases a short APTT may reflect a hypercoagulable state, potentially associated with increased thrombotic risk and adverse cardiovascular events. We prospectively evaluated the phenomenon of short APTTs in 113 consecutive samples compared with an equal number of age and sex-matched normal APTT samples. We found a significant difference in various test parameters including prothrombin time (PT), Factor (F) V, FVIII, FXI, FXII, von Willebrand factor (VWF) antigen and collagen-binding activity, and in the level of procoagulant phospholipids, as assessed using a novel assay procedure (XACT). Interestingly, there was a significant negative association for fibrinogen, and although elevated, there was no significant association for FIX. On the basis of identified consecutive samples having multiple low APTTs on several sequential days, a proportion of laboratory-defined short APTTs appear to represent in-vivo hypercoagulability. In conclusion, plasma from patients presenting with short APTTs is reflective of a complex hypercoagulant milieu that could feasibly contribute to thrombotic risk, and 20% or more of laboratory definable short APTTs appear to reflect in-vivo phenomenon.

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Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

A laboratory evaluation into the short activated partial thromboplastin time

Mina¹,

Favaloro

Mohammed

et al. 2010

Blood Coagulation &Amp; Fibrinolysis

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show abstract

“…Hypercoagulability due to high levels of coagulation factors such as FVIII, FIX, FXI and fibrinogen represents increasing recognized risk factors for venous thromboembolism [5], and these factors are cumulatively assessed by the APTT. FVIII contributes to platelet aggregation and fibrin formation via thrombin generation under low shear conditions [6] and has previously been shown to be elevated in samples yielding short APTTs [7]. Our group also recently reported on variously elevated procoagulant factors (factor V, FVIII and FXI) in such samples [8].…”

Section: Introductionmentioning

confidence: 59%

Relationship between short activated partial thromboplastin times, thrombin generation, procoagulant factors and procoagulant phospholipid activity

Mina

Favaloro²,

Koutts³

2012

Blood Coagulation &Amp; Fibrinolysis

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Short activated partial thromboplastin times (APTTs) are associated with thrombosis. However, what short APTTs actually represent in terms of possible mechanistic pathways is not well characterized. We have assessed thrombin generation as compared with levels of procoagulant factor (fibrinogen, V, VIII, IX, XI and XII) activities, von Willebrand factor level and activity using collagen binding, as well as procoagulant phospholipid activity, in 113 consecutive samples exhibiting a short APTT compared with an equal number of age-matched and sex-matched samples yielding a normal APTT. We found a significant difference in peak thrombin generation, velocity index and area under the curve between the two groups, and that thrombin generation markers correlated with the APTT, procoagulant phospholipid activity and several procoagulant clotting factors. We conclude that short APTTs represent a procoagulant milieu, as represented by heightened thrombin generation and several other heightened procoagulant activities, which may help explain the association with thrombosis.

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“…Variation in reagents, coagulometers, and operators but also in the nature of the mode of assay operation, i.e. clot-based assays, all contribute to the lack of consistency between assay results [20,21].…”

Section: Discussionmentioning

confidence: 99%

“…Despite this standardization, poor agreement among PT methods has been observed [22]. Variability in APTT reagent sensitivity for monitoring heparin has also been observed, resulting in a lack of correlation between assays for the same samples [20,21].…”

Section: Discussionmentioning

confidence: 99%