Methods of (i) reducing morbidity and/or mortality in a human patient undergoing cardiac surgery (ii) preventing, or reducing the risk of development of, LCOS in a human patient undergoing cardiac surgery or (iii) reducing the risk of, intensity of, or occurrence of, one or more postoperative adverse events in a human patient undergoing cardiac surgery. The methods can involve (a) a first period of administering to the patient levosimendan for about 1 hour, in which the administration of levosimendan during the first period is initiated: (i) before skin incision for the cardiac surgery, and (ii) at an infusion dose of about 0.2 μg/kg/min and (b) a second period of administering to the patient levosimendan for about 23 hours, in which the administration of levosimendan during the second period is initiated at an infusion dose of about 0.1 μg/kg/min.