Loss of consciousness is the most common sign of ventricular fibrillation.

Early signs and symptoms

A condition in which the lower chambers of your heart beat too fast (ventricular tachycardia) can lead to ventricular fibrillation. Signs and symptoms of ventricular tachycardia include:

  • Chest pain
  • Rapid heartbeat (tachycardia)
  • Dizziness
  • Nausea
  • Shortness of breath
  • Loss of consciousness

When to see a doctor

If you or someone else is having the above signs and symptoms, seek emergency medical help immediately. Follow these steps:

  • Call 911 or the emergency number in your area.
  • If the person is unconscious, check for a pulse.
  • If no pulse, begin CPR to help maintain blood flow to the organs until an electrical shock (defibrillation) can be given. Push hard and fast on the person's chest — about 100 compressions a minute. It's not necessary to check the person's airway or deliver rescue breaths unless you've been trained in CPR.

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 deliver a shock only when it's needed.

Nov. 01, 2014

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