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definition of MI was based on the new consensus document formulated by the Joint American-European Task Force for Redefinition of MI (18). All cardiac events were assessed and agreed upon by at least two of the investigators. Statistical analysis Student ttest and chi-square analyses were used to compare variables between groups of patients. Two-tailed Pearson’s correlation coefficient was used to correlate ischemia duration with cTn-I and CK-MB. Receiver-operator characteristic curve (ROC) analysis was used to assess the concordance between cTn-I and ischemia duration and to define the cutoff values of these variables associated with largest area under the ROC. All preoperative predictors of MI with p value <0.1 on univariate analysis were included in a multivariate logistic regression analysis. Forward stepwise conditional selection method (probability criteria for stepwise: entry = 0.05, removal = 0.1) identified the variables independently associated with PMI. Results summarizes the preoperative clinical features of all patients and demonstrates the relatively high incidence of CAD and cardiovascular risk factor typical to these patients. During 11,132 patient-hours of monitoring (60.7 ± 11.9 per patient), 38 patients (20.5%) had 66 ischemic episodes (1.7 ± 1.4 per patient, range: 1 to 8), all but one denoted by ST-segment depression. One patient had an episode of ST-segment elevation in leads L2, L3and aVF associated with ST-segment depression in V1to V3and aVL that lasted 24 min and was not accompanied by an elevation of cardiac markers. depicts the characteristics of myocardial ischemia and infarction in the 38 patients with ischemia. The duration of the longest ischemic events was 96 ± 127 min (range: 11 to 625 min), and the cumulative ischemia duration over the entire monitoring period was 150 ± 252 min (range: 11 to 1,150 min). In seven patients, myocardial ischemia was clinically suspected by the treating physicians and their ST-Guard data were disclosed in order to verify and treat ischemia. Four of these patients already had prolonged ST-segment depression on the ST-Guard at the time ischemia was clinically suspected and subsequently had PMI. ∗ p values for comparison between patients with and without MI. legend AAA = abdominal aortic aneurysm repair; ACE = angiotensin-converting enzyme; CABG = coronary artery bypass grafting surgery; CEA = carotid endarterectomy; ECG = electrocardiogram; IHD = ischemic heart disease; LEBP = lower extremity bypass surgery; MI = myocardial infarction; LVH = left ventricular hypertrophy by voltage criteria on ECG; PTCA = percutaneous transluminal coronary angioplasty. ∗ p value for the comparison between patients with and without MI. legend CK-MB = creative kinase-MB; MI = myocardial infarction. Postoperative MI Twelve patients (6.5%) sustained MI (cTn-I levels: 21.1 ± 26.5 ng/ml, range: 3.3 to 100.2). All infarctions were non-Q-type. In all 12 patients, the increase in cTn-I was detected either during (two patients) or within 18 h from a prolonged, transient ST-segment depression. All seven clinically evident cardiac events occurred in these patients: five patients had prolonged chest pain during peak ischemia, one of whom died from cardiac arrest seven days postoperatively; two patients developed congestive heart failure during the prolonged ischemia. In the other five patients, MI was asymptomatic. None of the 185 patients had new Q waves. In all patients with ischemia, including those with infarction, the ECG changes reverted completely to baseline, except for one patient in whom new T wave inversion persisted for >48 h. None of the 173 patients without MI suffered prolonged chest pain, cardiac failure or cardiac death during the hospitalization. Peak serum cTn-I concentration strongly correlated with
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