JR shared some very valuable information with you. I am glad it has helped you understand a bit better.
Working in the ER, before I retired, we did many EKGS; all machine interpretations had to be over-read by a physician. Our ER physicians preferred to turn off the interpretive function of the EKG machine if possible or at least ignored it.
One of the golden rules I have carried with me through my career was "look at the patient" - it served me well and I suspect the staff in your ER was doing just that.
Sorry to read of your difficulties with SSI, that is one topic I am not able to comment on, however, if you have serious heart problems your Dr. and attorney should be able to help you with your claim.