EMS Registry Ready

Sinus rhythm with a PVC couplet on an ECG strip

Two PVCs in a row, then the sinus rhythm again.

What to look for

Two PVCs in a row. Make it three or more in a row and you're looking at a run of ventricular tachycardia. After the pair, the sinus rhythm resumes on time.

Examples

Each strip is 6 seconds of lead II, drawn to scale (25 mm a second, 10 mm a millivolt), so you can count boxes the way you would on paper. Each one is a different example, measured below it.

Example 1 · lead II · 6 seconds
II25 mm/s · 10 mm/mV
Rate
83/min underlyingThe whole strip averages 95/min · 9 QRS complexes in 6 seconds × 10 = 90/min
Rhythm
Regular underneath, with early beats breaking it
P waves
Upright in II, uniform
P to QRS
1:1 for the sinus beats; the PVCs have no P wave
PR
0.17 s
QRS
0.11 s, narrow
PVCs
2 on this strip
Example 2 · lead II · 6 seconds
II25 mm/s · 10 mm/mV
Rate
79/min underlyingThe whole strip averages 90/min · 9 QRS complexes in 6 seconds × 10 = 90/min
Rhythm
Regular underneath, with early beats breaking it
P waves
Upright in II, uniform
P to QRS
1:1 for the sinus beats; the PVCs have no P wave
PR
0.14 s
QRS
0.08 s, narrow
PVCs
2 on this strip
Example 3 · lead II · 6 seconds
II25 mm/s · 10 mm/mV
Rate
92/min underlyingThe whole strip averages 104/min · 10 QRS complexes in 6 seconds × 10 = 100/min
Rhythm
Regular underneath, with early beats breaking it
P waves
Upright in II, uniform
P to QRS
1:1 for the sinus beats; the PVCs have no P wave
PR
0.15 s
QRS
0.08 s, narrow
PVCs
2 on this strip

Don't confuse it with

Want a new strip every time? The ECG Drill in the app draws a fresh, measured example on every try and steers you toward the rhythms you miss. It's part of the Paramedic level, and you can try 5 strips a day free.

Try the ECG Drill

Where the criteria come from

Others in the Ventricular group