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1. the act of separating or state of being separated.
2. the separation of a molecule into fragments produced by the absorption of light or thermal energy or by solvation.
3. segregation of a group of mental processes from the rest of a person's usually integrated functions of consciousness, memory, perception, and sensory and motor behavior, as in the separation of personality and aspects of memory or subpersonalities in the dissociative disorders or in the segregation of an idea or object from its emotional significance, as is sometimes seen in schizophrenia.
atrial dissociation independent beating of the left and right atria, each with normal rhythm or with various combinations of normal rhythm, atrial flutter, or atrial fibrillation.
atrioventricular dissociation a condition in which the atria and the ventricles contract independently of each other, without synchronization of their rhythms.
electromechanical dissociation pulseless electrical activity.
isorhythmic atrioventricular dissociation a cardiac rhythm in which the atria and the ventricles beat independently and at approximately the same rate.
a·tri·o·ven·tric·u·lar dis·so·ci·a·tion (AVD),, AV dissociation [MIM*209600]
1. any situation in which atria and ventricles are activated and contract independently, as in complete AV block;
2. more specifically, the dissociation between atria and ventricles that results from slowing of the atrial pacemaker or acceleration of the ventricular pacemaker at nearly (although rarely exactly) equal rates, each depolarizing its own chamber, thus interfering with depolarization by the other (interference-dissociation).
A condition in which the atria and ventricles contract independently, especially as resulting from the slowing of an atrial pacemaker or the acceleration of a ventricular pacemaker.
atrioventricular (AV) dissociation
a breakdown in the normal conduction of excitation through the heart, allowing the atria and ventricles to beat independently under the control of their own pacemakers.
atrioventricular dissociationThe independent depolarisation of the atria and ventricles, where atrial rhythm is controlled by one pacemaker and the ventricular rhythm is controlled by another, accompanied by atrioventricular dyssynchrony. Atrioventricular dissociation is not a primary condition in itself, but rather a symptom of an underlying dysrhythmia due to one of a number of causes that prevent the normal transmission of AV impulses:
• Slowing of the dominant pacemaker (usually the sinus node), which allows escape of a subsidiary (latent) pacemaker;
• Acceleration of a latent pacemaker, which wrests control of the ventricles and is accompanied by a pathologically enhanced rate of discharge;
• AV or 3rd-degree block, which prevents normal impulses from a dominant pacemaker from reaching the ventricles, allowing them to beat under the control of the subsidiary pacemaker.
atrioventricular dissociationAV dissociation Cardiology The independent depolarization of the atria and ventricles, where atrial rhythm is controlled by one pacemaker and the ventricular rhythm is controlled by another, accompanied by a loss of A-V synchrony. See Third-degree block.
the act of separating or the state of being separated.
independent beating of the left and right atria, each with normal rhythm or with various combinations of normal rhythm, atrial flutter or atrial fibrillation.
independent pacemakers in the atria and ventricles.
the tendency of a solute to dissociate in solution.
hepatocytes becomes detached from their neighboring cells, either generally or locally; a feature of death of the patient.