Summary
Alteration of the fibrinolytic system is considered to be important in the development
of deep venous thrombosis (DVT). Using specific assays for tissue plasminogen activator
(t-PA) activity, t-PA inhibitor (PAI) and t-PA antigen, we measured these activities
in 16 women who developed DVT during their pregnancies. A group of 24 healthy females
of comparable age was studied as controls. PAI was increased in 87% of these patients
compared to the healthy controls. In some of these patients a defect in release of
t-PA from vascular endothelium was found as well. The site at which blood was sampled
for analysis appeared to be an important criterion in the ex vivo assessment of functional
t-PA reserve and PAI levels, though relatively less so for the latter measurement.
The unaffected lower limbs, relative to the unaffected upper limbs, showed an increase
in PAI and a demonstrable decrease in t-PA release, both representing increased risk
factors for rethrombosis. The affected lower limbs showed similar but more accentuated
changes in these parameters.
Key words
Altered fibrinolysis - Deep vein thrombosis - Sampling site
