Ventricular Premature Beats

The arrow indicates a ventricular extrasystole (VES).

A VPB is an ectopic beat that origins from the ventricles. VPBs are hardly conducted by the specialised conduction system and therefore are broad. The QRS width is at least > 0.12 seconds, but often very broad at around 0.16-0.20 seconds.

Causes: e.g. ischemia, hypoxia, old scar tissue, idiopathic. 50% of healthy men have sporadic VPBs. The origin of the VPB can be derived from its form. A LBTB-configured VPB originates in the right ventricle. A RBTB-configured VPB comes from the left ventricle. The QRS duration of a VPB is > 0.12 seconds and can be as wide as 0.16-0.20 seconds.

A sequence of three or more extrasystoles is called a non-sustained ventricular tachycardia.

If more than one VPB is present on the ECG, they can be:

• monomorphic: all VPBs have the same configuration and thus have a mutual focus of origin.
• multiformic: the complexes have different configurations.