Diagnostic criteria

  Irregular impulses originate from different foci of the ventricles at a speed of 350-450/minute.

  There are different morphologies of the QRS complexes. No QRS complex looks like another.



Clinical significance

  Since there is no effective ventricular contraction, there is also no adequate cardiac output.

  If no immediate defibrillation is performed, this arrhythmia will rapidly result in death.

      There is no need to make synchronization during defibrillation since there is no regular rhythm

      to synchronize.




ECG 1. Ventricular premature beat (R-On-T) arises close to the peak of the T wave resulting in ventricular tachycardia (VT)
which then degenerates into ventricular fibrillation.

This ECG has been donated by Prof. Dr. Remzi Karaoguz to our website.

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ECG 2. Ventricular fibrillation (VF).

This ECG has been donated by Mehmet Kececi to our website.

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ECG 3a. The above rhythm tracing has been cropped from a 12-lead ECG.
If you had observed this tracing on a rhythm monitor, what would you think and how would you react?

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ECG 3b. Twelve-lead ECG of the same patient is depicted above. Although the tracing in ECG 3a suggests VF at a first glance,
the above 12-lead ECG shows atrial fibrillation and right bundle branch block. If the cardiac monitor shows unxpected rhythm,
first try to change the ECG lead.

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ECG 4. The rhythm tracing above was recorded by the defibrillator during defibrillation.

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