What Are The Ill Effects Of Having Magic Mushrooms?

i plan on taking magic mushrooms soon, ive done them 3 times before however now i have atrial fibrillatioon. i was wondering if there were known problems between the chemical in mushrooms (psilocybin) and this condition, or any interactions with the chemical and the medications im taking (coumadin 7.5mg, and multaq 400 mg. I've also had a mitral valve which was too small from birth and had open heart surgery for it, do mushrooms have any known dangers for this kind of condition