I agree 100% with vicki here; Fentanyl patches are very strong...you should only come off them under medical supervision.
Does your doctor know about the medical marijuana?
Hi and Welcome- No one is going to be able to predict how it will go for you if you detox cold turkey. Given your stroke history and the fact that you have a cardiac arrhythmia, I don't think it would be prudent.
Why don't you speak with your doctor who can offer you some options?