Dude if you went to the hospital 13 times and saw 3 different cardiologists, and they all cleared you with no issues, then I'd believe them. Granted it would scare me enough to stay off the juice but other than that you should take the drs advice if they are all saying the same thing. I don't see what a 14th hospital visit and 4th opinion from a cardiologist are going to do. They will tell you the same thing.
Thinking about it and worrying about it, is probably giving you anxiety. Anxiety attacks are often mistaken for heart attacks. My wife had an anxiety disorder and we went to the ER on 3 different occasions cause she was having similar symptoms as you. Never any heart issues.