Which EKG finding indicates a difference between accelerated idioventricular rhythm and junctional rhythm?

The characteristic that distinguishes accelerated idioventricular rhythm from junctional rhythm is the nature of the QRS complexes. In accelerated idioventricular rhythm, the QRS complexes are typically wide because this indicates that the impulse is originating from a ventricular focus rather than following the normal conduction pathway of the heart, which results in a longer duration of ventricular depolarization. A wide QRS complex suggests that the ventricles are being activated abnormally and at a slower rate compared to the normal conduction system.

In contrast, junctional rhythms typically present with narrow QRS complexes because the impulse originates from the junctional area, which allows for normal conduction through the ventricles, leading to quicker ventricular depolarization. Therefore, the difference in QRS complex width is a key distinguishing feature between these two rhythms. Understanding this feature is crucial for the appropriate interpretation of EKGs and for making informed clinical decisions.