A Case of Acute Total Obstruction of the Left Main Coronary Artery Presenting with Atypical Momentary Electrocardiogram Changes

Acute total obstruction of the left main coronary artery (LMCA) is a serious emergency condition requiring prompt diagnosis and treatment. Unless properly treated, it will likely progress to cardiogenic shock and a high mortality rate. We report a case of acute LMCA total obstruction presenting with atypical momentary electrocardiogram (ECG) changes including right bundle branch block with left axis deviation, and ST-segment elevation in aVR and aVL. We focus on the unusual ECG changes associated with LMCA obstruction which should be noted in order to ensure revascularization without delay, especially when this condition is accompanied by cardiogenic shock.