An atrioventricular dissociation characterized by independent and equally beating atrial and ventricular pacemakers, in the absence of a retrograde conduction. Isorhythmic atrioventricular dissociation (IAVD) is a rhythm disturbance in which atria and ventricles are driven by independent pacemakers at. Sometimes, patients may present for a routine evaluation and incidentally have an electrocardiogram demonstrate isorhythmic AV dissociation;.


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A transthoracic echocardiogram performed at the time revealed normal left ventricular size and systolic function with isorhythmic av dissociation regional wall motion abnormalities and no significant valvular disease. A Electrocardiogram ECG on presentation demonstrating an accelerated junctional rhythm with isorhythmic atrioventriculardissociation.

B The patient's baseline ECG. Points to ponder AV dissociation is most commonly associated with third-degree or complete AV block.


However, AV dissociation, in which two separate rhythms exist concurrently within the heart, can occur in other conditions. It can also occur when there is a pathologically high junctional or ventricular rate such as ventricular isorhythmic av dissociation VT with absence of retrograde VA conduction.


The final cause is Isorhythmic av dissociation dissociation due to interference; this occurs where there are two rhythms either atrial and junctional or atrial and ventricular occurring at similar rates and near simultaneously such that both anterograde and retrograde isorhythmic av dissociation fall into each other's refractory period; this is termed isorhythmic AV dissociation.

In our patient, the rhythm was initially misdiagnosed as an accelerated junctional rhythm with retrograde atrial activation.

Isorhythmic atrioventricular dissociation in Labrador Retrievers.

This is not correct as the P waves that follow the QRS complexes are positive in the inferior leads II, Isorhythmic av dissociation, avF indicating an inferior axis; this indicates they must be originating in the high right atrium. If these P isorhythmic av dissociation were due to retrograde conduction, the RP intervals would be constant.

Both fusion beats and capture beats may be present when either the atrial or ventricular rate becomes faster than the other with antegrade or retrograde conduction.

Both P waves and the QRS complexes look related with the P wave moving closer to and then farther away from the QRS, maintaining an illusion of a normal atrioventricular conduction sequence. Occasionally, the P wave might move into and get buried within the Isorhythmic av dissociation complex, only to move back out again in front of the QRS in the subsequent beats.

Isorhythmic A-V dissociation

The two pacemakers will remain independent as long as the SA node rate is bradycardic. When this rhythm occurs intermittently with normal sinus rhythm, it is isorhythmic av dissociation accrochage. When the isorhythmic dissociation is persistent, it is called as synchronization.

Synchronization has two distinct isorhythmic av dissociation like, the pattern which is characterized by a rhythmic fluctuation of the interval between the P and QRS waves, most often the P wave oscillating gradually back and forth across the QRS; that is, with periodically varying of P-R and R-P intervals.