squiggly lines

I learnt to read electrocardiograms! In a very basic sort of way. I didn't know how to diagnose myself when we found that my ECG was a mash of squiggly lines, that my heart rate rises and falls with my breathing, and that my Q-T is sometimes higher than my QRS. Although that was after I drank an entire can of coffee milk as an experiment. Heart rate became extremely irregular and sort of skipped all over the place. Which frightened no one, so I freaked out internally (yep that made my reading worse). My group were more concerned that our results wouldn't conform to predicted results. No one asked about my apparently abnormal heart. Although I honestly wouldn't know what is wrong with it either, but.