Comparison of Value of Leads from Body Surface Maps to 12-Lead Electrocardiogram for Diagnosis of Acute Myocardial Infarction

We aimed to develop 12-lead electrocardiographic (ECG) models testing ST-elevation criteria with QRST variables and compare their performance with the 80-lead body surface map (BSM) in detection of acute myocardial infarction (AMI). Because the prevalence of non–ST-elevation AMI is increasing worldwide, advances in early ECG detection of AMI are urgently needed. The study population was 755 consecutive patients presenting with ischemic chest pain from January 2002 to June 2004. All patients had electrocardiography and body surface mapping performed at initial presentation. AMI occurred in 519 patients (69%, cardiac troponin T or I level ≥0.1 ng/ml). Of these 519 patients, 303 (58%) had no ST-elevation on the initial 12-lead electrocardiogram. Ten patients were classified as having an “aborted AMI” and were included in the AMI analysis. The American College of Cardiology/European Society of Cardiology criteria for ST-elevation on 12-lead electrocardiogram identified 236 patients with AMI (sensitivity 45%, specificity 92%). Additional QRST features improved sensitivity (51% to 68%) but with decreased specificity (71% to 89%), with the optimal multivariate ECG model having a c-statistic of 0.75. The optimal BSM model identified 402 patients as having AMI (sensitivity 76%, specificity 92%, c-statistic 0.84). This improvement in sensitivity over the 12-lead electrocardiogram was due mainly to detection of ST-elevation in the high right anterior, posterior, and right ventricular territories and AMI in the presence of left bundle branch block. In conclusion, QRST variables added to criteria for ST-elevation result in improvement in sensitivity of the 12-lead electrocardiogram, although with decreased specificity. The BSM is superior in detecting AMI and demonstrates the importance of electroanatomic evaluation of patients with acute coronary syndromes.