Hi, I am a 29yr old healthy male that is active and has trained my whole life. I am 5' 7" and weigh 77kg. Anyway my question relates to something that happened to me randomly about 7 months ago, I had had a big night out on the town and the next day whilst grabbing something out of the fridge i got excruciating pain in my back then i got crazy sensations and a heavy and hard heartbeat. I sat down and the heart rate was very high but i breathed slowly and it decreased whilst my middle back pain remained. Anyway that was all over and besides being scared i forgot about it, then the next weekend i was watching a movie in bed when i suffered extreme palpatations and a racing heart rate and pins and needles up and down my arms with sweaty palms. I thought i was having a heart attack and got rushed to hospital in ambulance. They said my heart rate was 180 and blood pressure very high too. They ran ecg's and although it was fast they couldnt find anything conclusive and sent me home. It happened a third time randomly again whilst at work and i was rushed to hospital, my heart rate was super high and i had major pins and needles and a tight chest and sore back. They kept me in for 4 hours and did chest xrays, boodtests and ecgs but couldnt conculde anything and gave me valiums to slow down heart and sent me home with script for valium, they believed it to be anxiety related. Anyhow i quit caffeine and started eating even healthier and training more. It was good for few months then just last week I had a minor episode where i felt like i was going to faint and heart rate raced again then went away, to be on safe side I went to doctors and they did ecg but this time found I had a bundle branch blockage which wasnt present in any prior ecg's. What does this imply? The doctor said it was fine and sent me home. I am worried.