Premature atrioventricular junctional beats originate from the atrioventricular junction. These impulses can conduct both forward and retrograde, producing premature QRS complexes and retrograde P waves. The retrograde P wave can appear before (PR interval < 0.12 seconds), within, or after the QRS complex (RP interval < 0.20 seconds). The QRS complex typically has a normal morphology, but may vary if intraventricular conduction is aberrant. Premature atrioventricular junctional beats usually do not require treatment.
Figure 1 Premature atrioventricular junctional beats
The arrow indicates a premature atrioventricular junctional beat.