Glad to hear your dad is doing well. I've been only lurking lately (my year is up) but when I saw what else you posted about your dad's symptoms, I thought my two cents may be helpful...A couple years ago I was having chest pain along with numbness in my left arm and hand. I was taken by ambulance to the ER and didn't suffer a heart attack but after a follow-up with my regular doctor they found two things...1. (Via an eco cardiogram) Tricuspid regurgitation in my tricuspid valve. (It's where blood leaks back where it shouldn't)This isn't too serious but can give some pain. Some ppl later on have to get the valve replaced. 2. Acid reflux... and later I found out one of my co-worker's husband's has acid reflux and will get numbness in his arm and hand. I've found watching what I eat and taking my medicine helps. HTH!