Ventricular fibrillation occurs when the heart beats with rapid, erratic electrical impulses. This causes pumping chambers in your heart (the ventricles) to quiver uselessly, instead of pumping blood. During ventricular fibrillation, your blood pressure plummets, cutting off blood supply to your vital organs.
Ventricular fibrillation is an emergency that requires immediate medical attention. A person with ventricular fibrillation will collapse within seconds and soon won't be breathing or have a pulse. Emergency treatment for ventricular fibrillation includes cardiopulmonary resuscitation (CPR) and shocks to the heart with a device called a defibrillator.
Treatments for those at risk of ventricular fibrillation include medications and implantable devices that can restore a normal heart rhythm.
Loss of consciousness or fainting is the most common sign of ventricular fibrillation.
Early ventricular fibrillation symptoms
When to see a doctor
Portable automated external defibrillators (AEDs), which can deliver an electric shock that may restart heartbeats, are available in an increasing number of places, such as in airplanes, police cars and shopping malls. They can even be purchased for your home. Portable defibrillators come with built-in instructions for their use. They're programmed to allow a shock only when appropriate.
To understand how ventricular fibrillation happens, consider what should happen during a normal heartbeat.
What's a normal heartbeat?
Your heart is divided into four hollow chambers. The chambers on each half of your heart form two adjoining pumps, with an upper chamber (atrium) and a lower chamber (ventricle).
During a heartbeat, the smaller, less muscular atria contract and fill the relaxed ventricles with blood. This contraction starts when the sinus node — a small group of cells in your right atrium — sends an electrical impulse causing your right and left atria to contract.
The impulse then travels to the center of your heart, to the atrioventricular node, which lies on the pathway between your atria and your ventricles. From here, the impulse exits the atrioventricular node and travels through your ventricles, causing them to contract and pump blood throughout your body.
What causes ventricular fibrillation?
Most VT occurs in people with some form of heart-related problem, such as scars or damage within the ventricle muscle from a heart attack. Sometimes VT can last for 30 seconds or less (nonsustained), and not cause any symptoms, although it causes inefficient heartbeats. But, VT may be a sign of more-serious heart problems. If VT lasts more than 30 seconds, it will usually lead to palpitations, dizziness or fainting. Untreated VT will often lead to ventricular fibrillation.
In ventricular fibrillation, rapid, chaotic electrical impulses cause your ventricles to quiver uselessly instead of pumping blood. Without an effective heartbeat, your blood pressure plummets, instantly cutting off blood supply to your vital organs — including your brain. Most people lose consciousness within seconds and require immediate medical assistance, including cardiopulmonary resuscitation (CPR). Your chances of survival are better if CPR is delivered until your heart can be shocked back into a normal rhythm with a device called a defibrillator. Without CPR or defibrillation, death results in minutes. Most cases of ventricular fibrillation are linked to some form of heart disease. Ventricular fibrillation is frequently triggered by a heart attack.
During ventricular fibrillation, your ventricles quiver uselessly instead of pumping blood. ...
Several factors may increase your risk of ventricular fibrillation, including:
Tests and diagnosis
Because ventricular fibrillation is a life-threatening condition, it's unlikely you'd be diagnosed at a routine doctor's appointment unless you happened to collapse in the office. Ventricular fibrillation is always diagnosed in an emergency situation. Your doctors will know if you're in ventricular fibrillation based on results from:
Tests to diagnose the cause of ventricular fibrillation
Treatments and drugs
Emergency treatments for ventricular fibrillation focus on restoring blood flow through your body as quickly as possible to prevent damage to your brain and other organs. After blood flow is restored through your heart, if necessary, you'll have treatment options to help prevent future episodes of ventricular fibrillation.
Treatments to prevent future episodes
Lifestyle and home remedies
Adopting a heart-healthy lifestyle can help prevent episodes of ventricular fibrillation, primarily by reducing your risk of heart attack. A heart-healthy lifestyle includes:
Home automated external defibrillators (AEDs)
If you use an AED on someone, it's still critical that you call 911 or your local emergency services to get help on the way before you begin using the AED.
Last Updated: 2010-11-12
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