Cvirn Gerhard, Tafeit Erwin, Hoerl Gerd, Janschitz Michaela, Wagner Thomas, Juergens Guenther, Koestenberger Martin
Institute of Physiological Chemistry, Medical University of Graz, Austria.
Clin Lab. 2010;56(11-12):585-9.
The heparinase-modified thrombelastometry (HEPTEM) assay is a promising tool to assess the coagulation status of heparinised patients. The aim of our study was to examine the heparin neutralizing capability of the HEPTEM assay in plasma samples.
In the HEPTEM assay, blood or plasma samples become activated via the intrinsic pathway in the presence of a heparin processing enzyme.
We examined coagulation times (CTs) in the presence of increasing amounts (0-4 IU/mL) of heparin. We found that up to a concentration of 0.5 IU/mL, heparin is completely neutralized. However, CTs increased linearly in the presence of heparin concentrations higher than 0.5 IU/mL, indicating incomplete heparin neutralization in the standard HEPTEM assay.
We provide herein a mathematical procedure to correct the misleadingly prolonged CTs (for heparin > 0.5 IU/mL) for the HEPTEM assay performed in plasma samples to allow better estimation of the coagulation status in patients requiring intense anticoagulation (e.g., patients undergoing cardiac surgery).
肝素酶修饰血栓弹力图（HEPTEM）检测是评估肝素化患者凝血状态的一种有前景的工具。我们研究的目的是检测血浆样本中HEPTEM检测的肝素中和能力。
在HEPTEM检测中，血液或血浆样本在存在肝素处理酶的情况下通过内源性途径被激活。
我们检测了存在不同量（0 - 4 IU/mL）肝素时的凝血时间（CTs）。我们发现，在浓度高达0.5 IU/mL时，肝素被完全中和。然而，在肝素浓度高于0.5 IU/mL时，CTs呈线性增加，表明在标准HEPTEM检测中肝素中和不完全。
我们在此提供一种数学方法，用于校正血浆样本中进行HEPTEM检测时因肝素浓度>0.5 IU/mL而被误导延长的CTs，以便更好地评估需要强化抗凝的患者（如接受心脏手术的患者）的凝血状态。
