How does a junctional rhythm appear on telemetry, and what is the typical rate?

How does a junctional rhythm appear on telemetry, and what is the typical rate?

• A. P waves may be absent or inverted; QRS usually narrow; rate approximately 40-60 bpm.
• B. P waves preceding QRS normally; rate 60-100.
• C. Wide QRS with tachycardia; rate 100-120.
• D. No P waves or QRS; flatline.

Answer: (A)

A junctional rhythm arises from the AV junction, so the atria may be activated after the ventricles or not at all in the usual forward direction. On telemetry this typically shows P waves that are absent or inverted (retrograde atrial depolarization), and the QRS complex remains narrow because conduction through the His-Purkinje system is intact. The rate is usually slow, about 40-60 beats per minute, reflecting the intrinsic pacing of the AV junction rather than the SA node. This combination—absent or inverted P waves, narrow QRS, and a rate around 40-60 bpm—fits a junctional rhythm best. The other patterns describe normal sinus rhythm (P waves before QRS at 60-100 bpm), wide-QRS tachycardia, or asystole, which don’t match junctional rhythm.

A junctional rhythm arises from the AV junction, so the atria may be activated after the ventricles or not at all in the usual forward direction. On telemetry this typically shows P waves that are absent or inverted (retrograde atrial depolarization), and the QRS complex remains narrow because conduction through the His-Purkinje system is intact. The rate is usually slow, about 40-60 beats per minute, reflecting the intrinsic pacing of the AV junction rather than the SA node. This combination—absent or inverted P waves, narrow QRS, and a rate around 40-60 bpm—fits a junctional rhythm best. The other patterns describe normal sinus rhythm (P waves before QRS at 60-100 bpm), wide-QRS tachycardia, or asystole, which don’t match junctional rhythm.