Electrocardiographic differentiation between occlusion of the first diagonal branch and occlusion of the left anterior descending coronary artery

Purpose: We sought to electrocardiographically distinguish ST-segment elevation (STE)-acute myocardial infarction (AMI) caused by occlusion of the first diagonal branch (D1) from STE-AMI caused by occlusion of the left anterior descending coronary artery (LAD). Methods: We examined 29 patients with STE-AMI caused by DI occlusion (G-D) and 342 with STE-AMI caused by LAD occlusion (G-L). Results: G-D had a higher prevalence of STE >= 0.5 mm in each of leads I and aVL and a lower prevalence of STE >= 1 mm in each of leads V-1 through V-6 than G-L. The prevalence of STE >= 0.5 mm in lead aVL without STE >= 1 mm in lead V-1 was higher in G-D (82.1%) than in G-L (9.4%, P < .01). Conclusion: ST-segment elevation >= 0.5 mm in lead aVL without STE >= 1 mm in lead V-1 may be useful to distinguish STE-AMI caused by occlusion of the DI from STE-AMI caused by occlusion of the LAD. (C) 2009 Elsevier Inc. All rights reserved.