Definition of ventricular extrasystoles | Extrasystoles (tripping of the heart)

Definition of ventricular extrasystoles

Just like SVES, ventricular extrasystoles denote additional potentials that fall within the normal heart rhythm. In contrast to SVES, however, the potential here arises in ectopic (outside the normal ranges) excitation centers, which are located in the ventricles. A distinction is made between the VES in:

• Monomorphic extrasystoles: i.e. each extrasystole is deformed in the same way or simpler – all extrasystoles look exactly the same.

  Some of them occur in healthy people, some in people with heart disease.

• Polymorphic extrasystoles: the extrasystoles are differently deformed, look different. Here always a heart muscle damage is the basis (poly = much, morph = shape)Polymorphic ES are usually also polytopic, i.e. they are of different origin (topos = location)

Although extrasystoles are potentials that play in between, so to speak, outside of the normal rhythm, they often have a regular relationship to the normal rhythm. A distinction is made here: Non-stop tachycardia refers to a rapid heart rate of more than 100 beats per minute, but which lasts for less than 30 seconds.

If the phase of frequency increase lasts for more than 30 seconds, this is called persistent tachycardia. Persistent ventricular tachycardia is a life-threatening condition that can end in ventricular fibrillation (de facto cardiac arrest). Therefore, non-permanent tachycardia should always be taken seriously.

A special feature is the “R-on-T phenomenon”. If an extrasystole falls into the beat at a very short distance from the previous normal potential, it is possible that the extrasystole combines with the descending leg of the T-wave. The period of time in which the T-wave ends is also called the “vulnerable phase”, because in this phase a dangerous ventricular fibrillation (see below) can be triggered by incoming potentials.

These distinctions are summarized in the classification by Lown. The degree of VES according to Lown gives an indication of the prognosis of the diseases, but the classification has lost importance.

• Trigeminus or Couplets: Here, each normal potential is followed by two extrasystoles that would be pattern: N EE (compensatory pause) N EE.
• Salvos: If three or more extrasystoles follow each other without a normal potential in between, this is called a salvo. The pattern would be : N EEE (compensatory pause) N N N EEEEE. This is also referred to as non-pausing tachycardia.