Global fibrinolytic capacity assessed by the serum D-dimer test. Correlation between basal and stimulated values

Evaluation of fibrinolytic capacity is mostly done after stimulation by venous occlusion (VO) or 1-desamino-8-d-arginine vasopressin (DDAVP), either with global tests or with measurements of the specific fibrinolytic components. The serum D-dimer test has recently been described as a global fibrinolytic test in unstimulated individuals, and related to different levels of fibrinolytic activity. In the present study, we have compared the levels of serum D-dimer and t-PA before and after VO in order to see if the unstimulated values reflect the fibrinolytic capacity after stimulation. Twenty-eight healthy individuals and 126 patients with different metabolic disorders and/or coronary heart disease were included. Blood was drawn in a fasting state between 8 and 10 a.m. before and after VO for determinations of serum D-dimer after standardized coagulation, and of t-PA activity and antigen. There was a 7-fold increase in the median levels obtained after VO both for serum D-dimer and t-PA activity, whereas the increase in t-PA antigen was about 2.5 fold. The correlation coefficients between the levels of serum D-dimer, t-PA activity and t-PA antigen before and after VO were 0.63 (p < 0.001), 0.72 (p < 0.001) and 0.23 (p < 0.05), respectively. We conclude that the basal levels of t-PA and serum D-dimer to a certain degree reflect the fibrinolytic capacity after stimulation. Thus, the unstimulated serum D-dimer test, which reflects both t-PA and PAI-1, could be recommended as a global screening method for evaluation of the fibrinolytic potential.