I once had a panic attack and had several ECG's on one occasion I called the ambulance and the paramedic said I have an enlarged heart. I have a few ECG's since and I come back in the clear do you think the ambulance may have misread it first time? If was to have an enlarged heart does it mean I have heart failure? can an ECG give false positives? surely if I had a heart defect it would be mentioned again somewhere down the line.