Very clever, liked it a lot!

question: this could be done with transparent background to put it over a video. Nice tut. thanks for sharing

I’m going to be boring and point out some things which do not DIRECTLY relate to your tutorial, but which can be nice background information. By the way, I really enjoyed the tutorial, and the effect looks very good.

What you just made is an old-style, analog electrocardiograph display. The glow, which is entirely accurate for this type of ECG, is caused by a slow-glow picture tube where an electron stream is oscillating at a steady speed, as you described, and where the up-down movement is determined by the readings from the heart.

One of the more modern, and more colourful, displays you mentioned, would not have this glow… unless one wasted computing power on already ridiculously expensive medical equipment to add it in postprocessing, essentially doing the same on the ECG machine itself what you just showed how to do in the tutorial. Likewise, the line would probably not fade behind, but rather be cleared a certain distance prior to being drawn again.

Obviously, for making it look awesome in your movie clip, this is not essential information, but I figured someone, somewhere might be interested in knowing these things :-)

Another thing one could do for a bit of added realism, plus it being useful for the dramatic moments, is to add the ability to up the frequency of the heartbeat (for those moments when our hero has some kind of scary and/or exciting revelation happen while in his sick bed), or even make the line flat out as our unfortunate hero expires… or more likely, his plot hook girlfriend/boyfriend/father/sibling/pet/potted plant :-P

Mine’s won’t repeat :/ but great tutorial