This is a randomized controlled trial that compares the employment of 5% Albumin (ALB group) versus Fresh Frozen Plasma (FFP group) for priming as per standard protocol of extracorporeal circulation procedure. No modifications to the normal clinical management of the patient are planned. The primary endpoint is to reduce postoperative bleeding (registered as ml/kg in the first 12 postoperative hours). The secondary endpoints are to reduce transfusional requirements for all the blood products (packed red cells, fresh frozen plasma and platelets registered as ml/kg from the beginning of the extracorporeal circulation for up to 48 hours from the termination of the surgery), ventilation support and hospital stay duration. Safety endpoint is represented by the percentage of thromboembolic complications (stroke, peripheric, pulmonary and mesenteric thromboembolisms). Both the treatments employed in this trial are to be considered standard.