Figure 1.

Anti-fibrinolytics and PAR1 antagonists in cardiac surgery. (Left) A concern in cardiothoracic surgery is that, although antifibrinolytics are effective at reducing bleeding, might they not also present a concomitant risk of thrombosis? (Middle) The promise of PAR1 antagonists is that they can inhibit the action of thrombin on platelets while maintaining the hemostatic properties of thrombin in the coagulation cascade. (Right) The TRA-PCI study (phase II safety trial) seems to have borne out this early promise by noting no increase in TIMI bleeding but a 46% reduction in major adverse cardiovascular events after percutaneous coronary intervention. Aprotinin exhibits anti-thrombotic properties in on- and off-pump surgery by inhibiting thrombin-induced platelet activation through PAR1, yet it exhibits simultaneous hemostatic properties by blocking plasmin in the fibrinolytic pathway. tbn, thrombin.