This ECG was taken from a 49 year old man with insulin-dependent diabetes, with no complaints of cardiac symptoms.  The rest of this patient's history is lost.   This is a great ECG for demonstrating the flat ST segments and T wave inversion of ischemia due to coronary artery disease. The ECG changes are very noticeable in the lateral wall.  It is not known why the patient presented with sinus tachycardia.