What is the defining characteristic of a wandering atrial pacemaker?

A wandering atrial pacemaker is characterized by the presence of multiple different P wave morphologies in the electrocardiogram. This variation occurs because the impulse for each heartbeat can originate from different locations within the atria rather than from a single, consistent pacemaker site. As a result, each P wave may appear unique in shape and size, reflecting the different atrial foci responsible for initiating the impulses.

The presence of various P wave shapes is a key diagnostic criterion for this type of dysrhythmia, and it differentiates wandering atrial pacemaker from other conditions. In contrast, options that mention regular P waves, long QRS duration, or a fast heart rate do not accurately describe the nature of a wandering atrial pacemaker. Regular P waves suggest a more stable atrial pacemaker, while a long QRS duration typically indicates an issue with ventricular conduction. A fast heart rate could relate to other types of tachycardia but not to the wandering characteristic inherent to this specific dysrhythmia.