Which criteria is used to demonstrate wandering pacemaker?

A wandering pacemaker is characterized by the presence of variable atrial and ventricular rates, typically leading to a rhythm that can demonstrate rates often less than 60 beats per minute. This condition arises when the pacemaking activity shifts between different locations in the atria, causing fluctuations in heart rates. The fact that the rates are variable indicates that the impulses originate from different pacemaker sites, rather than a single, stable source.

In a wandering pacemaker, one might see P waves of different morphology due to the differing sites of origin, which would correspond with varying atrial rates. The variable rates and the lower overall heart rate are key indicators of this condition, distinguishing it from other types of abnormal rhythms which may maintain consistent rates or higher than normal heart rates.