A 46 year old lawyer with no previous cardiac history had sudden onset of severe oppressive left anterior chest pain while sitting down in his office. He is presenting to the Emergency Ward within 20 minutes from the onset of pain:

• Sinus rhythm
• Acute posterior infarct  
• Inferior injury pattern  

There are typical ECG findings of acute posterior infarct (R>S and marked ST depression in V2). There is ST elevation in the inferior leads suggestive of inferior injury, but no QRS pattern of inferior infarct.

The patient was immediately taken to cardiac catheterization lab. The right coronary artery was totally occluded near its origin. The lesion was crossed, dilated and stented. A 70% stenosis in middle segment of the circumflex artery was not dilated. The patient tolerated the procedure well and became free of chest pain. The following ECG is recorded 24 hours after the coronary angioplasty:

• Sinus rhythm

Compared with the previous tracings, there are evolutionary changes of acute inferior and posterior infarction.