Résumé
PURPOSE: New electrocardiographic criteria to predict the culprit coronary artery in acute inferior myocardial infarction have been developed. We tested the effectiveness of these criteria by verifying their diagnostic accuracy. METHODS: The seven electrocardiographic criteria are STsegment depressions (1) in leads I > 0.5 mm, (2) in aVL > 1 mm, and (3) in V6 under the isoelectric line; higher ST-segment elevations (4) in lead III than in lead II, (5) in V1 than in V6, (6) in the sum of V(1 + 2 + 3) > or = V(4 + 5 + 6); and (7) ST-segment elevation > 1 mm in V1, and were analyzed by comparing the ST-segment deviation with the location of the infarcted coronary artery in 43 patients with acute inferior myocardial infarction. RESULTS: The culprit coronary artery consisted of the right coronary artery in 72.1% of the cases, the left circumflex artery in 23.3% of the cases, and the left anterior descending artery in 4.6% of the cases. There was a significant correlation between the criteria and the culprit coronary artery, except for two criteria, ST-segment depression in lead I > 0.5 mm and elevation in lead V1 > 1 mm (p=0.00 to 0.02). Criteria such as ST-segment depressions in lead aVL > 1 mm and V6 under the isoelectric line and a higher ST-segment elevation in the sum of V(1 + 2 + 3) > or = V(4 + 5 + 6) had relatively high specificities (80%, 100%), but a low sensitivities (51.6%, 67.7%). Criteria such as higher ST-segment elevations in lead III than in II and in V1 than in V6 had not only high sensitivities (80.6%, 100%) and specificities (70%, 90%) but also relatively high diagnostic accuracies (95.1%, 82.9%). CONCLUSION: Higher ST-segment elevations in lead III than in II and in V1 than in V6 are sensitive & specific criteria for correctly predicting the culprit coronary artery in acute inferior myocardial infarction.