PB0162 - HEPA-Remove neutralises heparin in plasma efficiently and restores coagulability in heparinised plasmas.

Background: Heparins are widely used in the clinic to treat patients at risk of venous thromboembolism. To evaluate the coagulability of heparinised patients it is necessary to neutralise heparin in the patient samples before performing coagulation assays.
HEPA-Remove (5-Diagnostics, Basel, Switzerland) is a new peptide that binds sulphated glycosaminoglycans and neutralises the anticoagulant activity of heparins in vitro.

Aims: This study aimed to assess the capacity of HEPA-Remove to measure coagulation parameters in plasma samples that could otherwise not be quantitated due to the disturbing presence of heparins.

Methods: In reaction systems composed of purified components we assessed the ability of HEPA-Remove to neutralize the anticoagulant activities of heparin and LMWH with respect to the inhibition of thrombin and factor Xa.
In human plasma we studied the effect of HEPA-Remove on the endogenous thrombin potential (ETP) in the absence and presence of heparin, while applying both intrinsic and extrinsic triggering of coagulation. Similar studies were performed using the standard coagulation assays and a series of lupus assays.
Lastly, samples from patients on heparin therapy were tested to verify the ability of HEPA-Remove to neutralise the anticoagulant activities of heparin.

Results: The use of HEPA-Remove in a system of purified coagulation factors showed that HEPA-Remove effectively neutralised the activity of heparin towards thrombin and factor Xa. The addition of HEPA-Remove following the supplier’s instructions resulted in a negligible effect on coagulation times and ETP in the absence of heparin, while a normalisation of the coagulation times was observed for plasma samples which had been spiked with heparin or LMWH.

Conclusion(s): HEPA-Remove can be used to neutralise the anticoagulant activities of heparins in both purified reaction systems and in a plasma-environment. Use of HEPA-Remove allows the assessment of coagulability in patient plasma samples that otherwise cannot be interpreted because of the interfering presence of heparins.