As Dawn says, this is not a typical RBBB pattern and there are no definite P waves, whether normally conducted, dissociated or inverted due to retrograde atrial activation. As Dawn points out, the V2 and V3 electrodes appear to have been switched and in the lead that is labelled V3 I wonder if there is evidence of atrial fibrillation. Therefore, as an alternative to Dawn's suggestion, perhaps what we have here is AF with an accelerated idioventricular rhythm, possibly originating from the region of the left posterior fascicle.

There is atrial fibrillation, yet a precisely regular ventricular rhythm so we obviously have a third degree AV block. I see no evidence of digoxin in the ST segments, so I doubt digtoxicity is playing a role here - though we do have block with a slightly accelerated junctional rhythm. I believe that there is a preexisting RBBB with LAFB (I am not concerned about the monophasic-appearing R in V1 since the wide, slurred S in Lead I says it all). If this were a ventricular escape rhythm or an AIVR, there would be more of an RBBB-like morphology, but not a true RBBB. The last beat comes early and - with its different morphology - is most likely a PVC. The rhythm is a junctional escape rhythm (though a tad bit fast) which would still be more common than an AIVR and certainly more common in the presence of a third degree AV block. I also agree that V2 and V3 have been switched.