sinus rhythm with artifact
First Glance:
From across the room it looks a friendly sinus rhythm with exciting flutter in the lower lead.
Discussion:
This looks like a lovely sinus rhythm until halfway through when the lower lead shows ~300 bpm flutter-like waves. This is artifact, because the upper lead shows no deviation from the normal sinus rhythm. Even if we only saw the lower lead in isolation its large deflections rule out atrial flutter, and ventricular flutter is ruled out by marching the sharp QRS deflections through the flutter artifact.
This could be a cellphone ringing while on top of the V lead, or similar.
Final Impression?
Normal sinus rhythm @ ~90 bpm.
Management implications:
None.
The Take-home Point:
Many apparently brief ‘paroxysmal’ tachycardias can be simulated by electrical and movement artifact. Cell phones, tremor, and various electric devices can all look suspicious for atrial flutter, VT, VF, etc.
One star strip. Students should identify the rhythm correctly.