A new measure for in vivo thrombin activity in comparison with in vitro thrombin generation potential in patients with hyper- and hypocoagulability

Abstract The thrombin generation potential is an in vitro measure for the capacity of an individual to generate thrombin and recognized as a reflection of a hypo- or hypercoagulable status. Measurement of the in vivo thrombin activity, however, may be of clinical significance. We evaluated a new assay for in vivo thrombin activity and compared it to the in vitro thrombin generation potential in patients with hemophilia A (N = 15), oral anticoagulation for atrial fibrillation (AF) (N = 20), subjects with active cancer (N = 21), and healthy volunteers (N = 10). Thrombin activity was measured with a commercially available oligonucleotide enzyme capture assay in argatroban-stabilized plasma samples. Thrombin generation potential was determined with a commercially available assay in citrated plasma. Thrombin activity was detected in 17 (30.4 %) patients (mean 0.30 mU/ml [SD 0.80]), and in 39 patients (69.6 %) no thrombin activity was present. In cancer patients, thrombin activity was detected in 11 patients (52 %) (range 0.14–5.00 mU/ml) and was particularly increased in 3 patients with vessel-invasive tumors (1.2, 1.5, and 5.0 mU/ml). In AF patients, thrombin activity was only measureable in two patients (10 %) (recent hematoma [0.4 mU/ml] and recent ischemic stroke [1.5 mU/ml]). Thrombin activity was detected in four patients (27 %) with hemophilia (range 0.29–1.75 mU/ml), all of whom had received a factor VIII infusion on the same...
Source: Clinical and Experimental Medicine - Category: Research Source Type: research