A cardiac rhythm that is initiated from a pacemaker cell in the ventricles when other sites fail to initiate an electrical pulse.
Premature ventricular complex
An individual complex that originates from an area below the bundle of his and occurs earlier than the next expected complex of the underlying rhythm.
- Common and can occur in any rhythm.
Originate from a single site within the ventricles and, produce monomorphic complexes
Originate from different ventricular sites and produce polymorphic complexes.
- More dangerous because they are the result of increased irritability within the ventricles.
Quadrigeminy of PVCs
Occurs when every fourth QRS complex is a PVC
Trigeminy of PVCs
Occurs when every third QRS complex is a PVC
Bigeminy of PVCs
Occurs when every other QRS complex is a PVC
Describes two PVCs in a row that are not separated by a complex of the underlying rhythm.
Run of ventricular tachycardia
Occurs when three or more PVCs occur in a row, not separated by a QRS complex of the underlying rhythm.
R on T phenomenon
Additional term used to describe PVCs. Occurs when the R wave of the PVC falls on the T wave of the previous complex
The time during the cardiac cycle when the cardiac cells have repolarized to the point that some cells can be stimulated to depolarize again if the stimulus is strong enough
A dysrhythmia that originates from a single sit in the ventricles at a rate of 101 to 250 electrical impulses per minute.
Torsades de pointes
-Twisting of the points, life threatening dysrhythmia, type of ventricular tachycardia that looks similar to VT. The rate is often 120-240 electrical impulses per minute.
Lethal dysrhythmia that originates from many different sites within the ventricles.
- Neither the ventricles or the atria depolarize.
Waves have a higher amplitude and are more irregular.
Waves have less amplitude, indicating that fewer cardiac cells are able to respond to an electrical impulse
Lethal dysrhythmias that usually originate from a single site in the ventricles
- final attempt of the cardiac conduction system to initiate an electrical impulse from the ventricular muscle.
- 40 electrical impulses per minute.
Occurs when only atrial depolarization exists and there is no ventricular depolarization
- P waves are present and the p to p intervals are regular.
Occurs when there is a complete lack of electrical activity in both the atria and the ventricles.
- lethal dysrhythmia and Patient will not have a pulse