A Premature Ventricular Contraction (also referred to as a PVC) is an isolated contraction that occurs ‘early’ or premature in the ventricles affecting the natural heart cycle. PVC’s generally signify an disturbance in the electrical process of the hear that results in the ventricles contracting prior to the normal sinus / atrial protocol.
PVC’s are considered to be serious deviations from normal cardiac conduction cycles with impulses originating from the ventricles (in most cases prematurely). The typical causes can include organic cardiac disease, toxic effects of some anti-arrhythmic drugs, myocardial ischemia, or a severe electrolyte imbalance.
A Ventricular Ectopic Beat (VEB) or Premature Ventricular Contraction (PVC) is typically wider than the normal conduction of a Supraventricular Beat (> .12). PVC’s are generally originate in the ventricles from an ectopic focus rather than the atrium. A Multi-focal PVC can indicate a greater degree of irritability, electrical instability or disease state. The typical characteristics of a PVC can include no P wave, wide & bizarre shaped complex & often premature (early) with the presence of a complete compensatory pause.
Many clinical variations are seen. They may have P waves, as in the case of fusion beats. They may not have a compensatory pause, as in the case of interpolated PVC. They may not be wider than the patient’s normal complex, as in the case of chronic Bundle Branch Block (BBB). They may not be premature, as in the case of escape ventricular beats.
Clinical Significance
- Depends on presence of cardiac disease.
- Can indicate ventricular irritability.
- Frequency of occurrence (>5 per min) indicates a level of irritability.
- Multifocal versus unifocal VEBs also indicate extent of ventricles effected (more areas of irritability).
Premature Ventricular Contraction (PVC) CardiacMonitoring.com
Strip Preference
- Select an 8 second strip at time of occurrence and center the ventricular or wide abnormal complex.
- Extract examples of various multi-focal PVC activity when present.
Single Isolated Premature Atrial Contraction (PAC) with 2 Isolated Premature Ventricular Contractions (PVC’s)
For more information, click – ECG Arrhythmia Guide
