A chronic posterior wall infarct is characterized by a tall R wave in V1 (R/S >1.0). There is also a rightward axis.
Graphic 68277 Version 2.0
Normal ECG
Normal electrocardiogram showing normal sinus rhythm at a rate of 75 beats/minute, a PR interval of 0.14 seconds, a QRS interval of 0.10 seconds, and a QRS axis of approximately 75°.