Wow, that must have been scary.I'm glad he's in remission. I found out I had it when I finished a workout and my heart rate wouldn't go below 140. After lying on the floor for 20 minutes and it still didn't slow down I ended up calling 911 and getting an ambulance ride to the emergency room.
In my dad's case, he's always been a hard worker, but he was dropping a lot of weight and didn't have energy. I remember we were on vacation when I was a teenager and we were on a hike and he stopped to take a break. He was leaning against a large rock, sweating profusely and breathing heavily. I said to him, "Dad, it's not worth dying over!" He looked up at me with that little smirk of his and said, "It isn't?!"
Good old dad. Always has a good sense of humor, even when he's suffering.