Ventricular fibrillation

Ventricular fibrillation. Ventricular fibrillation is a very serious arrhythmia that can lead to death if it is not treated urgently. It is one of the most frequent causes of death after a myocardial infarction.


[ hide ]

  • 1 How is it produced?
  • 2 Symptoms
  • 3 Diagnosis
  • 4 Treatment
  • 5 Prevention
  • 6 Source

How is it produced?

Under normal conditions the heart contracts rhythmically and synchronously. This contraction is the result of an electrical impulse that is generated in the atrium, reaches the ventricle, and results in a heartbeat. In an arrhythmia, an alteration of this mechanism occurs that leads to the heart not contracting regularly, generating a rhythm disorder. The contraction of the ventricles pumps the blood to the rest of the body. In ventricular fibrillation, the heart rhythm is very fast and chaotic (up to 300 beats per minute) and is characterized by not being able to cause an effective heartbeat. Thus, the lack of contraction of the ventricles causes the blood to barely be pumped from the heart, causing a collapse of the cardiovascular system and cardiac arrest.

The most common cause of VF are heart diseases, mainly diseases of the arteries coronary and myocardial infarction. Diseases that cause serious metabolic disturbances such as lack of oxygen or electrolyte imbalance can trigger this type of arrhythmia.


VF manifests suddenly, with the absence of a pulse, heartbeat, and blood pressure; the absence of blood supply causes loss of consciousness, loss of skin coloration, and dilation of the pupils.


When the described symptoms appear and before an unconscious patient, the diagnosis is confirmed with the electrocardiogram that shows a characteristic record of the chaotic activity of the ventricle and with the verification of the absence of vital signs.


Ventricular fibrillation should be treated as an extreme medical emergency and treatment should be started immediately. If a VF is suspected, urgent medical help must be requested.

The indicated treatment is cardioversion. An electrical device called an external defibrillator delivers an electrical shock to the heart of a certain intensity to try to regain normal heart rhythm. Immediate cardioversion can be very effective if the heart is not badly damaged. In many public places (such as airports, sports complexes) there are defibrillators for public use in an emergency.

In addition, maneuvers called cardiopulmonary resuscitation should be started immediately in order to restore the patient’s respiratory and cardiac function and thus maintain blood supply to the brain. These maneuvers are a combination of regular chest compressions along with insufflations of air into the patient’s mouth. As soon as possible, hospital life support measures will be continued, including:

  • Orotracheal intubation and patient ventilation.
  • Monitoring (control) of vital signs: heart rate and rhythm, respiratory rate, blood pressure and blood oxygen concentration.
  • Administration of intravenous drugs (such as adrenaline) to restore and maintain heart rate and blood pressure.
  • The prognosis and recovery of the patient, especially at the brain level, will depend on the speed with which the treatment is established to restore blood flow to the different territories of the body , the most sensitive being the brain. Therefore, it is a medical emergency that requires immediate attention and a referral to a hospital.


Leading a healthy lifestyle, avoid alcohol, snuff, drugs and stress helps prevent diseases of the heart . It is very important for the prognosis and the survival of the patient to establish the treatment as soon as possible. In patients at risk for this type of arrhythmia, a device called an implantable cardioverter defibrillator can be placed in the chest that controls the heart rhythm and allows it to be restored if it detects an episode of VF.


Leave a Comment