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Ventricular fibrillation

Ventricular fibrillation

Ventricular fibrillation (VF) is a life-threatening cardiac arrhythmia characterized by the uncoordinated electrical activity of the heart. This leads to an inability of the heart to effectively pump blood, leading to a sudden drop in blood pressure and insufficient oxygen supply to the body. It is a medical emergency and requires immediate attention to restore normal heart rhythm.

Cause: Ventricular fibrillation is caused by abnormal electrical activity in the heart's ventricles. This can be caused by underlying heart diseases, such as coronary artery disease, congestive heart failure, and cardiomyopathy, or it can be caused by certain medications, electrolyte imbalances, or structural problems with the heart.

Symptoms: The primary symptom of ventricular fibrillation is sudden, uncoordinated contractions of the heart. This results in a lack of blood flow to the body and can cause dizziness, lightheadedness, confusion, chest pain, shortness of breath, and/or loss of consciousness.

Treatment of ventricular fibrillation is focused on restoring normal heart rhythm. This is usually done through the use of external defibrillation, which involves applying an electrical shock to the chest to reset the heart’s electrical activity. Other treatments may include medications to restore normal heart rhythm; in some cases, a pacemaker may be necessary.

It is important to seek immediate medical attention if you experience symptoms of ventricular fibrillation. Early detection and treatment can help prevent further complications and even death.

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  • American Heart Association. (2021). Ventricular Fibrillation. Retrieved from
  • Mayo Clinic. (2020). Ventricular Fibrillation. Retrieved from
  • National Heart, Lung, and Blood Institute. (2020). Ventricular Fibrillation. Retrieved from