This ECG is from a patient with chest pain.  We have no other information about the patient.  The rythm is atrial fibrillation with a ventricular response of about 113/min.  There is  ST elevation in aVR, with ST depression in all other leads, except V1 and aVL.  V1 is probably caught between showing us ST elevation from the base of the heart (like aVR) and ST depression from the anterior wall (like V2).  Therefore, the ST is flat.  aVL is often elevated in proximal LCA lesions, as well.

This pattern in a person with chest pain is associated with severe acute coronary syndrome (ACS), often with conditions that cause cardiogenic shock.  Proximal left coronary artery obstruction or severe triple vessle disease are likely.