Premature Ventricular Complex (PVC)

A premature beat arising from an ectopic focus within the ventricles.

AKA: ventricular ectopics, ventricular extrasystoles, ventricular premature beats, ventricular premature depolarisations.

Origin of Ectopic Beats

Ventricular Ectopics

Electrocardiographic Features

PVCs have the following features:

Discordance

Appropriate discordance describes a pattern of repolarisation abnormality (typically seen with LBBB, paced rhythms, VT) in which the ST segment and T wave are directed opposite to the main vector of the QRS complex:

Classification of PVCs:

The origin of each PVC can be discerned from the QRS morphology:

PVCs often occur in repeating patterns:

Clinical Significance

PVCs are a normal electrophysiological phenomenon not usually requiring investigation or treatment. Frequent PVCs may cause palpitations and a sense of the heart “skipping a beat”. In patients with underlying predispositions (e.g. ischaemic heart disease, WPW), a PVC may trigger the onset of a re-entrant tachydysrhythmia — e.g. VT, AVNRT, AVRT.

Frequent PVCs are usually benign, except in the context of prolonged QTc, when predispose to malignant ventricular arrhythmias eg. Torsades de Pointes due to “R on T” phenomenon

Causes


Management

In absence of structural cardiac disease

In the absence of structural disease, prognosis is debatable with some studies suggesting frequent PVCs are associated with increased risk of sudden cardiac death and others suggesting higher mortality during exercise.

In presence of structural cardiac disease

Control of underlying cardiovascular disease is mainstay of treatment.


References include:
https://litfl.com/premature-ventricular-complex-pvc-ecg-library/