Which of the following is NOT a characteristic of the wandering pacemaker rhythm?

Which of the following is NOT a characteristic of the wandering pacemaker rhythm?

• A. P wave shape varied
• B. Atrial rate less than 100
• C. Regular ventricular rhythm
• D. Irregular ventricular rhythm

Answer: (C)

Wandering pacemaker is a specific type of arrhythmia characterized by the shifting of the electrical pacemaker site among different areas within the atria. One of its hallmark features is the variability in the shape of the P waves, which occurs as the impulse is generated from different locations in the atria. This results in P waves of differing morphology, often presenting a mix of different shapes on the electrocardiogram.

In wandering pacemaker, the atrial rate typically remains below 100 beats per minute, distinguishing it from other rhythms like atrial flutter or fibrillation, where the atrial rates are higher.

A key aspect of wandering pacemaker is its irregular ventricular rhythm, which reflects the varying timing of atrial impulses reaching the ventricles due to changes in the pacing site. Thus, the presence of an irregular rhythm is a critical characteristic of this arrhythmia.

The regular ventricular rhythm does not align with the defining features of wandering pacemaker since the condition inherently includes irregularity in the timing of ventricular contractions resulting from the shifting pacemaker activity. It is this irregularity that makes the option regarding a regular ventricular rhythm the correct answer, as wandering pacemaker is characterized by irregularity rather than regularity.