My Previously Healthy 80yr Old Mother Developed A-fib, And Now

my previously healthy 80yr old mother developed a-fib, and now possibly CHF (swollen feet, SOB). This all happenined shortly after being dx with left atrial cancer (sarcoma?). She was on hydrochorothiazide about a month ago and developed nosebleeds (needing cauterization). Her meds are now furosemide, pantoloc, xarelto and bisoprolol. She is concerned that the lasix will cause her nose to bleed again. Your thoughts? Also, she wants to know if she can take Red Reishi mushroom exctract capsules to help with her energy level, insomnia (which has lead to some depression and anxiety). Thank you!