Which of the following rhythms presents with a normal PR interval?

The rhythm that presents with a normal PR interval is the Wandering Atrial Pacemaker. This rhythm is characterized by the presence of varying P waves due to the pacemaker activity shifting between different atrial sites. In this case, the PR interval remains normal because it reflects the time taken for the electrical impulse to travel from the atria to the ventricles through the AV node, which functions properly in this scenario.

In contrast, other rhythms listed do not demonstrate a normal PR interval. For instance, the Accelerated Idioventricular rhythm typically has a wide QRS complex and no P wave, leading to an absence of a measured PR interval. Agonal rhythms present as very disorganized and usually imply severe cardiac compromise, often showing irregular and ineffective contractions, which makes it difficult to measure a PR interval. Lastly, Ventricular Fibrillation is characterized by chaotic electrical activity in the ventricles with no identifiable waveforms or intervals, indicating that there is no PR interval present.

Understanding these distinctions helps in recognizing the significance of the Wandering Atrial Pacemaker's normal PR interval in distinguishing it from other cardiac rhythms.