Ventricular fibrillation is always diagnosed in an emergency situation. A pulse check will reveal no pulse if sudden cardiac death occurred.

Tests to diagnose and determine the cause of ventricular fibrillation include:

  • Electrocardiogram (ECG or EKG). This quick and painless test measures the electrical activity of your heart. Sticky patches (electrodes) are placed on your chest and sometimes your arms and legs. Wires connect the electrodes to a computer, which displays the test results. An ECG can show if your heart is beating too fast, too slow or not at all. If you're having an episode of ventricular fibrillation, the ECG usually shows a heartbeat of about 300 to 400 beats a minute.
  • Blood tests. Blood tests can be done to check for enzymes that leak into the bloodstream when the heart is damaged by a heart attack.
  • Chest X-ray. An X-ray image of your chest allows your doctor to check the size and shape of your heart and its blood vessels.
  • Echocardiogram. This noninvasive test uses sound waves to produce images of your heart's size, structure and motion.
  • Coronary catheterization (angiogram). To determine if your coronary arteries are narrowed or blocked, a dye is injected through a long, thin tube (catheter) that's inserted through an artery, usually in your groin area, to the heart's arteries. The dye makes your arteries show up more clearly on X-ray, revealing areas of blockage.
  • Cardiac computerized tomography (CT). During a cardiac CT scan, you lie on a table inside a doughnut-shaped machine. An X-ray tube inside the machine rotates around your body and creates images of your heart and chest.
  • Cardiac magnetic resonance imaging (MRI). This test uses a magnetic field and computer-generated radio waves to create detailed images of blood flow in the heart. During a cardiac MRI, you lie on a table that slides into a long tubelike machine.


Ventricular fibrillation requires emergency medical treatment to prevent sudden cardiac death. The goal of emergency treatment is to restore blood flow as quickly as possible to prevent organ and brain damage.

Emergency treatment for ventricular fibrillation includes:

  • Cardiopulmonary resuscitation (CPR). CPR mimics the pumping motion of the heart and keeps blood flowing through the body. First call 911 or your local emergency number. Then start CPR by pushing hard and fast on the person's chest — about 100 to 120 compressions a minute. Let the chest rise completely between compressions. Continue CPR until an automated external defibrillator (AED) is available or emergency personnel arrive.
  • Defibrillation. This treatment is also called cardioversion. An automated external defibrillator (AED) delivers shocks through the chest wall to the heart. It can help restore a normal heart rhythm. As soon as an AED is available, apply it and follow the prompts. If you're not trained to use an AED, a 911 operator or another emergency medical operator may be able to give you instructions. Public-use AEDs are programmed to recognize ventricular fibrillation and send a shock only when needed.

Other treatments for ventricular fibrillation are given to prevent future episodes and reduce your risk of arrhythmia-related symptoms. Treatment for ventricular fibrillation includes medications, medical devices and surgery.


Drugs to control your heart rhythm (anti-arrhythmics) are used for emergency or long-term treatment of ventricular fibrillation. If you're at risk of ventricular fibrillation or sudden cardiac death, your doctor may prescribe medications to slow and control your heartbeat.

Surgery or other procedures

Surgery or medical procedures to treat ventricular fibrillation include:

  • Implantable cardioverter-defibrillator (ICD). An ICD is an implanted device that constantly monitors your heart rhythm. If it detects a very fast heartbeat or a quivering heart, it sends out shocks to stop the episode and reset your heart's rhythm. The battery-powered device is implanted near your left collarbone during a minor surgery. One or more flexible, insulated wires (leads) from the ICD run through veins to your heart.
  • Cardiac ablation. This procedure uses heat or cold energy to create tiny scars in your heart to block the abnormal electrical signals that cause ventricular fibrillation. It's most often done using thin, flexible tubes called catheters inserted through the veins or arteries. It may also be done during heart surgery.
  • Coronary angioplasty and stent placement. If your ventricular fibrillation was caused by a heart attack, this procedure may reduce your risk of future episodes of ventricular fibrillation.

    Doctors insert a long, thin tube (catheter) through an artery, usually in the groin, to a blocked artery in your heart. A balloon on the tip of the catheter briefly inflates to widen the artery, restoring blood flow to the heart. During the procedure, the doctor may place a metal mesh stent into the artery to help it stay open.

  • Coronary bypass surgery. This open-heart surgery improves blood flow to the heart. It may be done if your ventricular fibrillation was caused by coronary artery disease. During bypass surgery, the surgeon takes a healthy blood vessel from your leg, arm or chest and connects it below and above the blocked arteries in your heart. This creates a new pathway for blood to flow through.

Clinical trials

Explore Mayo Clinic studies testing new treatments, interventions and tests as a means to prevent, detect, treat or manage this condition.

Lifestyle and home remedies

Lifestyle changes that help keep your heart as healthy as possible include the following:

  • Eat a healthy diet. Heart-healthy foods include fruits, vegetables and whole grains, as well as lean protein sources such as soy, beans, nuts, fish, skinless poultry and low-fat dairy products. Avoid added salt (sodium), added sugars and saturated fats.
  • Exercise regularly. Get at least 150 minutes of moderate aerobic activity or 75 minutes of vigorous aerobic activity a week, or a combination of moderate and vigorous activity. The guidelines suggest that you spread out this exercise during the course of a week.
  • Don't smoke. If you need help quitting, talk with your doctor about strategies to help.
  • Keep your blood pressure and cholesterol levels in a healthy range. Maintaining a healthy body weight can help control blood pressure and cholesterol. Take medications as prescribed to manage high blood pressure or high cholesterol.
  • Limit alcohol. Too much alcohol can damage your heart. If you choose to drink alcohol, do so in moderation. For healthy adults, that means up to one drink a day for women and up to two drinks a day for men.
  • Get regular checkups. Take your medications as prescribed and have regular follow-up appointments with your doctor. Tell your doctor if your symptoms worsen.

Coping and support

Some abnormal heart rhythms can be triggered by emotional stress. Taking steps to ease stress and anxiety can help keep your heart healthy.

Some types of complementary and alternative therapies may help reduce stress, such as:

  • Yoga
  • Meditation
  • Relaxation or mindfulness techniques

Getting support from your loved ones also is key to managing stress.

June 02, 2021
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