I really thought Zoloft was finally working, but yesterday I had one of my biggest panic attacks yet. I ended up in emerge because of palpitations and the nurse said my heart rate was irregular but in the 80s. My EKG showed that my heart rate was fine. I'm so discouraged and confused. I know anxiety can cause palpitations, but can it actually cause an irregular beat? She even asked me if I drank a lot of caffeine that day.