My longest SVT episode was 2.5 hours. I had two before that but thought it was a simple reaction to medication I was taking. I was at a concert and i felt that flutter and got really hot. I eventually (after realizing that this was a serious problem) had to call my parents to come get me because I could barely see, let alone drive. They took me to the hospital and that is where I got diagnosed. They gave me this medication that stopped my heart and made me feel horrible.