Coagulation system. TF, tissue factor; F, coagulation factor (e.g. FVII); TFPI, tissue factor pathway inhibitor; C1inh, C1 esterase inhibitor; TAT, thrombin–antithrombin complexes; vWF, von Willebrand factor. The letter ‘a’ denotes activated enzymes. Solid lines indicate activation, dashed lines inhibition, and dashed grey lines indicate thrombin-induced feedback activation.