Hi! I'm seeing a couple of issues with this. First, is the provider actually performing separate 12 lead and 3 lead ECGs at separate encounters on the same DOS? What is the logic behind adding the modifier 59 to 93040? What you are describing really doesn't make much clinical sense (in my opinion). A 12 lead ECG (93000) would be considered a complete study so there would need to be a well documented rationale to also try and report a 3 lead (93040). Second, I don't think it would be appropriate to add modifier 26 to 93040 as there is already a code for reporting the professional interpretation and report only, 93042. I've coded for several cardiology practices and I have never seen anyone attempt to report ECGs this way; without better documentation I think this would be considered an attempt at unbundling.
Hope this helps...