Approach Considerations
The standard workup of the patient presenting with atrioventricular (AV) dissociation includes taking a thorough history and performing a physical examination in addition to reviewing pertinent laboratory data, reviewing electrocardiograms/rhythm strips, and longer term monitoring. To help determine if AV dissociation or AV block is present when there is isorhythmic activation, changing patient positions and physical activity can help.
No specific radiologic imaging studies are needed for AV dissociation.
Laboratory Studies
There is no specific laboratory evaluation for atrioventricular dissociation, but in select cases, obtaining the following studies may be useful to consider if clinically indicated:
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Serum potassium levels
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Serum creatinine levels
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Digoxin levels
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Troponin levels, if recent or current ischemia
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Thyroid stimulating hormone level [18]
Electrocardiography
An electrocardiogram (ECG), prolonged rhythm strips, and Holter or event recorder monitoring are the most commonly used modalities to diagnose atrioventricular (AV) dissociation.
Please refer to the following ECG images of interference and isorhythmic AV dissociation along with sinus bradycardia with junctional escape rhythm. See Background for more details.
Atrioventricular Dissociation. Significant slowing of the sinus node allows for a subsidiary pacemaker (atrioventricular [AV] junction) to activate, causing AV dissociation.
Atrioventricular Dissociation. This rhythm strip reveals interference atrioventricular dissociation, as there is a P wave conducting to the ventricle in the third and seventh beats, whereas the P wave fails to conduct to the ventricle in the other beats.
Atrioventricular Dissociation. Isorhythmic AV dissociation. There is AV dissociation with independent atrial and ventricular conduction at similar rates.
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Atrioventricular Dissociation. Significant slowing of the sinus node allows for a subsidiary pacemaker (atrioventricular [AV] junction) to activate, causing AV dissociation.
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Atrioventricular Dissociation. This rhythm strip reveals interference atrioventricular dissociation, as there is a P wave conducting to the ventricle in the third and seventh beats, whereas the P wave fails to conduct to the ventricle in the other beats.
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Atrioventricular Dissociation. Isorhythmic AV dissociation. There is AV dissociation with independent atrial and ventricular conduction at similar rates.
