I couldn't find any info on what borderline means, but I did find this....
"
Poor R wave progression is a finding on an EKG that can reflect either an artifact of the way that the EKG leads are placed or reflect a previous heart attack. However, your symptoms could still be from coronary artery disease; the only way to know for sure would be a cardiac catheterization. "
I don't know if that helps or not.
Good Luck!
-Angela