ECG library
Second-degree AV block, Mobitz I (Wenckebach)
core25 mm/s · 10 mm/mV · synthetic tracing
100%
Calipers:2000 ms50.0 small boxes30 bpm if R-RDrag the orange markers. One small box = 40 ms.
Key findings
- Progressive PR prolongation
- Grouped beating
- Narrow QRS
Learning points
- Grouped beating on the rhythm strip is Wenckebach's visual signature.
- Nodal block (Mobitz I) is usually benign and often vagal or drug-related; infranodal block is not.
Connected