Ekg shows old inferior infarct and abnormal r wave progression, but echocardiogram is completely normal.. what are the chances the ekg is wrong? this is the 3rd ekg in 3 months (i have anxiety) and only this one time the inferior infarct showed up?

Ecg's are highly sensitive on lead placement, settings and software used for automatic interpretation. An isolated automatic ( not confirmed) reading for an old infarct is relatively common and cannot be correlated most of the times with actual history and/or findings on other tests/exams. Proper follow up with a cardiologist would be best in trying to clarify and dissipate anxiety away.