ECG of the week 30

I thought this was tricky because it would be easy to call this CHB.

This is really just a 1° AVB. What you're seeing is a junctional escape (40bpm) rhythm producing a repeated dysrhythmic sequence  of two junctional excapes and a ventricular capture.  There is no BBB, there are subtle differences in the QRS "escape complexes" (vs the captured ones) .  The captured beats tell us that if her sinus rate dropped to about 60, she would have 1:1 conduction.