[Monitoring of heparin therapy with activated recalcification time]

In in-vivo- and in-vitro-examinations the activated recalcification time, the recalcification time of the plasma, the partial thromboplastin time and the thrombin time were compared concerning their suitability for the control of a heparin therapy. The laboratory methods tested considerably differed in their sensitivity compared with heparin and in the possibility of a quantitative statement. The use of a certain laboratory method depends on the indication for a heparin therapy and on the heparin concentration in the blood to be expected. While thrombin time, recalcification time of the plasma and the partial thromboplastin time are suited only for the proof of lower heparin concentrations, the activated recalcification time allows also the proof of higher heparin concentrations in the blood.