Compared with the control group , the serum HO-@ was significantly increased at @ , @ , @ , @ h after the heart valve replacement surgery in both the RIPerC and RIPostC groups ( P < @ ) ; the SCr , BUN , urinary NGAL and serum iron values were decreased at @ , @ , @ , @ h after the heart valve replacement surgery in both the RIPerC and RIPostC groups ( P > @ ) .