You know how sometimes you learn about something and suddenly you can't stop seeing every instance of it being done completely wrong? Yeah, that's me and ECGs right now. I've learned the structure of a normal ECG output, and so now I can't see (incorrect) fictional ECG output without going "Wait a second, that's not how those work!"
A minor correction to my post here. Nothing major, but I did get the heartbeat slightly wrong. Q is actually a small downwave at the beginning of the QRS complex. My point still stands, particularly as I got most of the ECG right, but it's worth correcting. Also, there's something called a U wave. Not majorly important, usually doesn't even show up, but, that's there, in case you cared.