Junctional bradycardia or junctional escape rhythm need to be differentiated from other bradycardia conditions which has the bundle of His or the ventricles as their pacemaker compensating for the failed SA node.

• Complete heart block : In complete or third degree heart block there is sinus node activity but failure of conduction through the AV node. There are P waves dissociated from the ventricular complexes with a rate faster than the ventricular rate that differentiates complete heart block from junctional escape beat where there is absence of P waves.
• Idioventricular rhythm : An ventricular escape beat is a form of cardiac arrhythmia, in this case known as an ectopic beat. If there are only one or two ectopic beats, they are considered escape beats. If this causes a semi-normal rhythm to arise it is considered an idioventricular rhythm. A wide QRS because of ventricular origin of the idioventricular rhythm differentiate it from junctional bradycardia where the QRS is narrow.
• Premature ventricular contraction : An absence of P wave activity, associated with a widened QRS complex resembles a PVC and occuring after a pause of variable duration is characteristic of PVCs.