Electrocardiographic Prediction of the Localization of the Culprit Lesion in Left Anterior Descending Coronary Artery in Patients with Acute Anterior Myocardial Infarction

Anterior myocardial infarction (MI) generaly is due to occlusion of the left anterior descending (LAD) coronary artery. The more proximal culprit lesion will cause extended myocardial involvement. Although coronary angiography is the gold standard to determine the site of the culprit lesion, it is not practical in the acute period. To predict the site of the culprit lesion, we used electrocardiography. Thirty-nine patients (five women, 34 men) with an average age of 53±9 years who were admitted to GATA Coronary Care Unit with acute anterior MI between January 1992 and December 1994 and in whom we were subsequently able to detect the culprit lesion by coronary angiography, were included in this study. Patients were divided into 2 groups (proximal and distal) according to the site of culprit narrowing in relation to the origin of the first diagonal branch. Electrocardiograms of the groups were evaluated in regard to ST-segment changes. ST depressions in leads II, III and aVF in the proximal group were more significantly pronounced than in the distal group (P values for leads II, III, and aVF were 0.003, 0.025 and 0.037, respectively). Logistic regression analysis of the ST depression =0.5 mm in leads II, III, aVF and V6 revealed a predictive accuracy of 92% and 50% (overall accuracy 79%) in estimation of the culprit lesion proximal and distal to the first diagonal artery, respectively. In conclusion, the culprit lesion in patients with acute anterior MI with an ECG showing ST depressions in leads II, III and aVF will generally be located proximal to the first diagonal artery.