This 75 year old patient presented to the Emergency Department with crushing substernal chest pain and the electrocardiogram shown below.

She was taken immediately to the cardiac catheterization lab for emergency coronary angiography and possible direct angioplasty/stenting for an Acute Myocardial Infarction. On arrival to the lab, her blood pressure was stable and she was awake and alert. Angiography of the coronary system is shown below:

Injection of the left main coronary artery is shown here. The left main is functionally occluded and there is faint flow into the Left Anterior Descending Artery (LAD). There is no flow in the Circumflex artery.