Peak serum TnI concentration was similar in the intervention and usual care groups ( median -LSB- interquartile range -RSB- : @ -LSB- @-@ @ -RSB- vs @ -LSB- @-@ @ -RSB- ng litre ( -@ ) ; P = @ ) , and no differences were observed in serum TnI concentrations over @ h ( repeated-measures anova , P = @ ) .