J wave can be thought of as a fish hook. The EKG guy has a nice little video on BER for anyone who wants to learn more, where he mentions its presence in V4.
Awesome! Could you apply the same principles to proximal lad occlusion vs pericarditis, in other words is the an s or j wave also present in v2+3 in pericarditis as a point to differentiate those two entities?
If you want to drive home the difference between a J-point and a J-wave, it is important not to call the J-pint a J-wave in the first few examples. Otherwise, it's a very helpful video