TG boosts recurrent VTE prediction

18 August 2008

MedWire News: Measuring thrombin generation (TG) may help identify patients with the greatest risk for recurrent venous thromboembolism (VTE), say Italian investigators.

The team examined the impact of the hypercoaguability factor in 254 patients with a first episode of idiopathic VTE who were followed-up for 2.7 years after discontinuing vitamin K antagonist treatment.

The patients' endogenous thrombin potential (ETP) was measured 1 month after treatment was stopped, and the peak thrombin and lag-time were determined in the presence and absence of thrombomodulin (TM).

Overall, 13.4% of the patients experienced recurrent VTE during follow-up.

Analysis showed that patients with an ETP >960 nM/min or a peak thrombin time in the presence of TM >193 nM were 3.41 and 4.57 times more likely to experience recurrent VTE than those with an ETP <563 nM/min or TM <115 nM.

In addition, patients with a thrombin lag-time <14.5 minutes were 3.19 times more likely to experience recurrence than those whose lag-time was >20.8 minutes.

The presence of TM improved the hazard ratio for recurrent VTE in all three assays, note Armando Tripodi (University and IRCCS Maggiore Hospital, Milan) and colleagues.

Writing in the Journal of Thrombosis and Haemostasis, they conclude: "The possible advantage of the thrombin generation assay over the other individual parameters... rests on the fact that thrombin generation may be considered as a laboratory parameter reflecting the composite effect of most of the other individual risk factors."

J Thromb Haemost 2008; 6:1327-1333