Figure 2: The clinical course of activated clotting time (ACT), infusion rate of argatroban, and timing of argatroban bolus administration (grey arrow) during the operative period of the second case. Thrombus formation was found in the right atrium and the reservoir of cardiopulmonary bypass (CPB) at ‘*’. Plasmapheresis was started at the time of weaning from CPB and performed during ‘⇔’. ACT : Activated Clotting Time, CPB : Cardiopulmonary Bypass.