Heart block · Critical
2nd Degree AV Block, Mobitz II
● Live · lead II25 mm/s · 10 mm/mV
II
10-second rhythm strip · count the boxes
RateAtrial normal; ventricular slower
RegularityIrregular when beats drop
P wavesNormal, regular P-P
PR intervalConstant on conducted beats, then a sudden dropped QRS
QRSOften wide (infranodal disease)
Key features
- Constant PR with intermittent non-conducted P waves
- Frequently coexists with a bundle branch block