As a third year medical student I've learned that (1) mastery comes from experience and practice (2) if you take a systematic approach, you're less likely to miss things (3) and understanding is more reliable than memory. All of these lessons can be applied to anything, but I find them especially relevant to understanding and reading electrocardiograms better known as EKG or ECGs.
While I'm far from an expert on the subject, here are the best resources I've found for understanding and gathering information from this vital medical tool.
(1) I had an attending refer to this book simply as "Dubin," and I had no clue what he was talking about. I think that shows just how little of it I read as a first year (even though I already had it on my book shelf!) and part of the reason cardiology and EKG reading were so challenging for me. While I still haven't made it completely through the book just yet, Dubin breaks down every aspect of electrocardiogram tracings and their associated cardiovascular pathology into easy to digest explanations with lots of built in repetition and diagrams. This is a great non-intimidating way to start understanding and reading EKG tracings.
(2) I recommend you follow-up "Rapid Interpretation of EKGs," with this EKG library. This is a great free resource from "Life in the Fast Lane" medical blog. It includes an A-to-Z diagnosis list, explanation of basic terminology and principles, tons of examples, clinical cases, quizzes, and links to other print and online resources. The website is also a great educational resource and includes critical care insights for many other topics, so be sure to bookmark it for future reference, especially if you're interested in emergency medicine.
(3) Ignore the official reading at the top of the EKG print out. It's tempting to take a peak and then try to find the "ischemia" or "LV hypertrophy," but don't cheat yourself. Be a little uncomfortable and a little wrong and miss a few things in the beginning. That's ok. That's how you learn. Try to recognize the patterns in the waves on your own without bias. The more experience you get doing it, the easier it will become. I've searched all over and haven't been able to find another way. It really is understanding what each part of the tracing is capturing and practice.
(4) And finally calipers...because how else are you going to measure and compare intervals? You may even earn yourself an extra point if your attending asks for them. Just make sure you're careful. They have a safety cap, but they're super sharp and would probably leave a mean puncture wound; they're definitely not the kind of thing you want to forget in your bag walking through airport security!
(5) Finally, for real this time, be patient with yourself. I've seen many tracings that I thought were pathological but were actually normal, whether it be from artifact, misplaced leads, or just normal variation. That's why it's extremely important to go back to basics and be systematic when you're reading them each and every time! Good luck!
Have you found any other tools or resources to help with understanding and reading EKGs? Leave them below!