Epsilon-aminocaproic acid promotes the release of alpha2-antiplasmin during and after cardiopulmonary bypass.

This double-blind, randomized study compared the mechanisms by which low-dose aprotinin and epsilon-aminocaproic acid (EACA) inhibited fibrinolysis during cardiopulmonary bypass surgery. D-dimer levels during and after bypass were similar, indicating an equivalent inhibition of fibrinolysis. Effects on tissue plasminogen activator release were not associated with the inhibition of fibrinolysis by either drug. Treatment with EACA was associated with a substantial release of endogenous alpha2-antiplasmin, particularly 1 h after bypass. Compared with the aprotinin group, higher levels of the plasmin-alpha2-antiplasmin complex in the EACA group confirmed an increased inhibition of plasmin by alpha2-antiplasmin. In conclusion, it is hypothesized that EACA inhibited fibrinolysis by stimulating the release of the patients' own alpha2-antiplasmin.