Premature Ventricular Contractions
PVCs are premature ventricular activations arising from ventricular myocardium or the specialized conduction system; mechanisms vary by substrate.
1. What might the surface ECG tell us?
PVC morphology, bundle-branch pattern, axis, transition and other features can suggest a region of origin.
2. What might we see intracardially?
Local ventricular electrograms and sometimes specialized potentials are assessed relative to QRS onset.
Technologist mindset
Describe the sequence before naming the mechanism. Ask what is earliest, what follows, whether atrial and ventricular activation are linked, and whether the pattern changes with pacing.
3. Pacing clues
Pacing may be used for pace mapping, comparing paced QRS morphology with the clinical PVC when appropriate.
4. Mapping concept
Activation mapping seeks the earliest local activation preceding the surface QRS; pace mapping can supplement activation data.
5. Ablation concept
When clinically indicated, ablation targets the arrhythmogenic focus or relevant substrate while accounting for nearby structures.
Quick knowledge check
What is the best learning sequence for PVC?
Professional reference
Open professional guidance →
Founder-authored educational summary. External expert review is not implied unless specifically stated.