Hi Ken,
Sorry to hear about the stress test results, but I wouldn't worry too much quite yet.
It is true that you can have scarring from old heart attacks as well a long list of other problems: hereditary cardiomyopathy, sarcoidosis, rheumatic disease.....etc.
It is important to know how big the scar is and what territories (i.e. what major arteries supply the area with scar). If the scar is consistent with a typical vascular distribution of a heart attack, it may be real and you may have had a silent heart attack. If it is not consistent with an appropriate vascular distribution, it may be a false positive study.
At this point you need to see a cardiologist. Not only to determine if the interpretation is correct but because if you have heart disease, you will need specialized care (statins, beta blockers, aspirin).
The key is seeing the old study or repeating a new one – and I would let a cardiologist do the reviewing rather than a general practitioner.
I hope this helps….