Fibrinolysis is the mechanism leading to fibrin clot dissolution in order to restore vessel patency or to dissolve a clot following the healing of a vessel injury. It involves various proteins, that act either as inhibitors, delaying clot dissolution, (PAI-1, Alpha-2-antiplasmin, TAFI, HRGP…), or as activators that enable fibrin polymer breakdown (tPA, uPA, plasminogen). Plasminogen plays the central role in that process: after its activation into plasmin by either tissue plasminogen activator (tPA) or urokinase (uPA), it cleaves fibrin polymer.

Hyperfibrinolysis has been associated with mild to severe bleeding tendency, especially during surgery and invasive procedures. It is associated with increased morbidity and mortality.

Hypofibrinolysis is a risk factor for thrombosis and may become a predictive marker of venous thromboembolism and arterial thrombosis.