Hello and thank you for using HCM.I carefully read your question and I understand your concern.
I will try to explain you something and give you my opinion.
If you previously had a
heart attack than you are at higer risc of having another one.
A previously heart attack might have coused a muscle heart demage, leading to redused heart function.A reduced heart function or what we call cardiac insufficiency may give symtoms like difficulty in breathing deeply,palpitations periferic edema, hipotension,
fatigue ect.
You should also know that typical heart pains have some characteristics. They usually are retro-sternal pains like squizzing , tightness or heaviness. They may irradiate to both arms , neck and jaw. They last from 5-20 minutes.
So, if you are experiencing chest pains, difficulties in breathing deeply than I would say that you definitely need to seek medical advise.
If I was your treating doctor I would recommend some examination like a electrocardiogram, a cardiac echo to evaluate heart function,valves, a full blood analyze to exclude electrolyte imbalances.
After this simple examination we can create an idea what we are dealling whith and how to treat it.
Hope I was helpfull.
Best regards,Dr.Ervina.