Heart block · Stable
1st Degree AV Block
● Live · lead II25 mm/s · 10 mm/mV
II
10-second rhythm strip · count the boxes
RateUsually normal
RegularityRegular
P wavesNormal, one per QRS
PR interval> 0.20 s, constant
QRSNarrow
Key features
- Every P conducts, just slowly
- PR > 1 large box