Hello and welcome to the forum
. Your right, that is a lot to absorb all at once. I would think that your cardiologist will look at all your problems and then make a recommendations re a plan of care for you. AS you probably know your PFO has been with you all of your life but has not appeared to cause you any major problems up to this point. Starting you on medications feels like the right approach from what I know. I am not a physician however.
My husband was dx with cardiomyopathy in September with mild mitral valve regurge which was a big shock to us too.
Anytime we learn we have had a heart attack we become concerned so your worries are certainly valid. Do keep working with your cardiologist and consider a second opinion if you feel it is warranted. You deserve to have the best information and options available to you to prevent any other events.
Take care and do let us know how you are doing. My prayers are with you.