Educational Electrocardiographic Findings in a Man with a Totally Occluded Left Main Coronary Artery

Significant left main coronary artery (LMCA) disease and total occlusion of the LMCA are very important cardiovascular emergencies and indicate an urgent need for invasive treatment strategies. Furthermore, a significantly higher risk of catheter-based procedural complications in these patients must be taken into consideration. All of these facts are important issues in estimating significant LMCA disease using electrocardiography (ECG) findings, the fastest and easiest method for the diagnosis and evaluation of acute coronary syndrome. We present here a case report of a 52-year-old man admitted to our emergency department with anterior myocardial infarction complicated by cardiogenic shock. There were Q waves and ST elevations in leads V1-V6, D1, aVL and aVR, as well as marked ST depressions in the inferior leads with right bundle branch block (RBBB) and left anterior fascicular block (LAFB) on the ECG. The left main coronary artery (LMCA) was totally occluded with no antegrade or retrograde coronary flow on coronary angiography.