Symptoms, Tests and Diagnosis of Ventricular Fibrillation


Symptoms and diagnostics of ventricular fibrillationVentricular Fibrillation always starts without any precursors and leads to immediate cardiac arrest:

  • Dizziness and weakness appear in 3 seconds after the onset of fibrillation;
  • When normal heart contractions stop, blood circulation also ceases; in 15-20 seconds patient loses consciousness showing no signs of cardiac function (heart sounds, pulse and blood pressure in large arteries);
  • In 40-50 seconds, there appear typical convulsions, urinary incontinence and grunting respiration. At the same time pupils start dilating;
  • Breathing gradually slows and then stops, clinical death occurs. During this phase it is essential to use electrical defibrillation (by means of electric discharge) and the sooner it is applied the better the prognosis.

If within 4 minutes, no effective cardiac output is achieved, then irreversible brain damage develops because oxygen is not supplied to the brain. After that an irreversible state - biological death – occurs.

Tests and Diagnosis

Ventricular Fibrillation is suspected if a person suddenly loses consciousness and no pulse, cardiac contractions as well as blood pressure are detected. It is extremely difficult to differentiate Ventricular Fibrillation and cardiac arrest due to the similarity of their clinical symptoms. 

Therefore, Ventricular Fibrillation or asystole is diagnosed on the basis of ECG - electrocardiographic examination.



Next chapter: Resuscitation procedures

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