My holter monitor showed i49.8 other specified cardiac arrhythmia is this bad? if they cant identify what type of arrhythmia it is? i go to an electrophysiologist in 2 days. nervous?

You are understandably nervous regarding next steps. The cardiac electrophysiologist is the specialist that will discuss findings so far and the next step that most likely will be inserting a loop recorder in your chest. That will clarify the type of arrhythmia and its relation with your symptoms as well as possible treatment if needed.

i49.8 is an ICD-10 code used to justify the reason and insurance coverage for the Holter. It does not mean anything from a diagnostic standpoint. It would not be the diagnosis of the results- there should be an actual report of the findings that specifically says the rhythm, any other rhythms, how fast/slow the heart rate, any pauses, etc. Would not worry until evaluated/explained by EP.