In their study consisting of coronary artery bypass graft (CABG) patients recruited from 4 major trials, Mahaffey found that creatine kinase-myocardial band (CK-MB) elevations following CABG surgery are independently associated with an increased risk of mortality in patients with non–ST-segment elevation acute coronary syndromes, especially if the peak CK-MB level is > 5 x the upper limit of normal (ULN).