Ventriculo-atrial Dissociation
Independent electrical activity between ventricles and atria, typically observed during ventricular tachycardia.
Full Definition
A condition where the ventricles and atria beat independently of each other, most commonly seen during ventricular tachycardia when the ventricular rhythm is faster than the intrinsic atrial rhythm and there is no retrograde conduction to the atria. This dissociation is a key diagnostic criterion for ventricular tachycardia and helps differentiate it from supraventricular tachycardia with aberrancy. Ventriculo-atrial dissociation can be identified on surface ECG by the presence of independent P waves that are not related to the QRS complexes, and it strongly supports a ventricular origin of wide-complex tachycardia.
Usage
Usage note: Hyphenate compound adjective form; can be abbreviated as 'VA dissociation' in appropriate contexts.
In Context
- "The presence of ventriculo-atrial dissociation during wide-complex tachycardia confirmed the diagnosis of ventricular tachycardia." — ECG interpretation report
- "Intermittent capture beats were observed despite ventriculo-atrial dissociation during the sustained arrhythmia." — EP study findings