ORMC Progressive Care Unit (PCU) Practice Test

Focus on the device delivering impulses. Failure to pace shows up on ECG as no pacing spikes at all. If the pacemaker isn’t delivering impulses, you won’t see the vertical pacing markers that would normally precede a QRS or a P wave. The heart then relies solely on its intrinsic rhythm, which may be slower or irregular.

In contrast, pacing with capture means you’ll see a pacing spike followed by a QRS complex (and possibly a P wave if atrial pacing). Pacing spikes present but without a following QRS indicate loss of capture, not failure to pace. Extraneous spikes without a captured beat would look different too. So the absence of pacing spikes specifically signals failure to pace. If that occurs, check the pacemaker function, leads, and battery, and notify the care team.