Localization of the culprit artery in inferior myocardial infarction: Influence of the point of measurement of ST segment.

BACKGROUND: There are several approaches widely used in the localization of the responsible artery in inferior myocardial infarction. However, the existing papers show differences in the point where the ST segment is measured. The purpose of our investigation is to analyse the influence of the point at which elevation of the ST segment is measured on the results of these algorithms. METHODS: We analysed the 12­lead electrocardiograms of 90 consecutive patients with inferior myocardial infarction. The ST segment elevation or depression was measured at the J-point and at 80 ms, and three algorithms were applied to predict the culprit artery with both measurements. Sensitivity, specificity, the area under the curve, and the kappa index of agreement were analysed to compare each algorithm at the J-point and at 80 ms. RESULTS: The area under the curve was better at the J-point than at 80 ms in two algorithms (0.696 vs. 0.635, p < 0.043, and 0.754 vs. 0.661, p < 0.045) and did not change in one. Agreement between the J-point and 80 ms was suboptimal in all three algorithms (0.71, 0.65, and 0.58). CONCLUSIONS: The result of different algorithms to detect the culprit artery in inferior STEMI patients can change significantly depending on the point where ST elevation or depression is measured.