Recognize findings on electrocardiography of a left main occlusion, a finding that often requires coronary artery bypass grafting.
ST elevation of at least 1 mm in aVR, in combination with diffuse and horizontal ST depression, indicates left main occlusion, which often requires coronary artery bypass grafting, not primary coronary angiographic revascularization.
Without carefully looking at the patient and the findings on ECG, it is possible for the healthcare professional to mistake the unusually widespread ST depressions on ECG for pericarditis with PR elevations (e.g., assuming the ST segments to be the baseline with comparative PR elevation instead). However, ST elevation in aVR of more than 1 mm in combination with aVR higher than V1 should lead to a high suspicion of left main occlusion.
New ST elevation in aVR (an easily missed feature) is always concerning for extremely serious and widespread cardiac ischemia. Left main or proximal occlusion of the left anterior descending artery, severe triple vessel disease, and global ischemia can all cause ST elevation in aVR.