PB0629 - The validation of new global fibrinolysis capacity assays in high tPA concentration situation and the comparison with thromboelastgraphy

Background: Global fibrinolysis assay is the method which activates coagulation reaction with tissue-type plasminogen activator (tPA) and detects fibrinolysis time of the clot. This assay is useful to investigate the global coagulation and fibrinolysis reactions simultaneously.

Aims: Recently, two kinds of global fibrinolysis assays of clot-fibrinolysis waveform analysis (CFWA) and global fibrinolysis capacity (GFC) were developed. In this study, the validation of these two assays was performed and the comparison against thromboelastgraphy (TEG) was also investigated.

Methods: The fibrinolysis times of CFWA and GFC were detected as CFWA-Lys and GFC-Lys in the total 151 samples spiked with tPA at the concentration of 0, 100, 500 and 1000 ng/mL, respectively. The comparison was also investigated in the methods of extrinsic pathway and intrinsic pathway of TEG by 77 and 74 samples, respectively. Four parameters including clotting time (CT), amplitude after 10 min (A10), maximum clot firmness (MCF), and Lysis index after 30 min (LI30) in TEG were used for the comparison.

Results: CFWA-Lys and GFC-Lys were significantly shortened in tPA high concentration samples, in especially the concentration of 500 and 1000 ng/mL. The correlation coefficients against CT, A10, MCF and LI30 in TEG extrinsic pathway were 0.092, 0.620, 0.618, and 0.497 for CFWA-Lys and 0.175, 0.731, 0.691, and 0.890 for GFC-Lys, respectively. In the intrinsic pathway, these values were 0.263, 0.574, 0.627, and 0.481 for CFWA-Lys, and 0.013, 0.745, 0.803, and 0.901 for GFC-Lys, respectively.

Conclusion(s): Both global fibrinolysis assays showed shorter fibrinolysis times in high tPA concentration samples, and CFWA-Lys and GFC-Lys were highly correlated with the parameters of clot firmness like A10 and MCF. It was considered that these assays reflected tPA concentration and clot firmness in the assay and would be useful to investigate the fibrinolysis status.