What does AV pacing refer to in an ECG?

AV pacing refers to a pacing mode that stimulates both the atria and ventricles, which can be inferred from the relationship between the pacing spikes and the P waves on an electrocardiogram (ECG). In this particular pacing configuration, a pacing spike is placed before the P wave to trigger atrial contraction, followed by another pacing spike that occurs before the QRS complex to ensure ventricular contraction, happening after the P wave.

This results in a consistent pacing sequence where the atrial pacing occurs just prior to the P wave and the ventricular pacing occurs subsequently with a specific timing relative to the P wave and the QRS complex. The dual nature of AV pacing—addressing both atrial and ventricular activity—contributes to maintaining proper coordination between these cardiac chambers, consistent with the physiological relationship in normal heart rhythm.

The correct interpretation of AV pacing thus encompasses both before and after the P wave, allowing for synchronized contraction of the heart's chambers, which is crucial for effective cardiac output.