ECG-based estimation of area at risk in acute myocardial infarction

We hypothesized that not only the location but also extent of myocardial ischemia (area at risk, AAR) during acute myocardial infarction could be estimated from the spatial distribution of ST-segment deviations in the ECG. Standard 12-lead ECGs and SPECT images were obtained from 75 patients. Precordial ST-segment deviations were organized according to spatial orientation. An ST-profile was obtained: a semicircle of ST-deviations centered on the ST-injury vector. Spatial features of the profile were calculated, the R wave vector magnitude was obtained, and an automated method of patient separation into culprit artery groups was developed. A linear regression model between optimal features and AAR yielded: r = 0.64(p <;0.01). AAR extent can be estimated from the magnitude of ST-deviations and R wave. The spatial distribution of ST deviations is indicative only of the location of AAR, not of extent.