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Ventricular Tachycardia


The Manual's Editorial Staff

Reviewed/Revised Jul 2022 | Modified Sep 2022
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Your heart is a muscle that pumps blood through your body. Your heart rate is how fast your heart beats. Your heart should always have a regular, rhythmic beat, like the ticking of a clock.

Your heart has four chambers. The atria are the two upper chambers in your heart. The ventricles are the two lower chambers in your heart. The atria pump blood into the ventricles. The ventricles pump blood to your lungs and your body (see also Biology of the Heart Biology of the Heart The heart is a hollow organ made of muscle. The heart and blood vessels are part of your cardiovascular system. Your heart pumps blood through your blood vessels Blood carries oxygen and nutrients... read more ).

Special pacemaker cells in a part of the atria called the SA node (sinoatrial node) send out regular electrical signals to your heart muscle to make it contract.

The Conduction System

Your heart's conduction system has tiny strips of tissue sort of like electrical wires. The conduction system carries the pacemaker signals to the rest of your heart. The signals must get to all your heart muscle cells at just the right time so your heart gives a good, strong beat that pumps blood properly.

What is ventricular tachycardia?

Sometimes ventricular tachycardia is only 3 or 4 ventricular premature beats Atrial Premature Beats An atrial premature beat is an extra heartbeat caused by electrical activation of the atria (upper chambers of the heart) from an abnormal site before a normal heartbeat would occur. (See also... read more in a row, and then your heart returns to a normal rate and rhythm. Sustained ventricular tachycardia is when the abnormal rhythm lasts more than 30 seconds. Sustained ventricular tachycardia can go on for a long time.

What causes ventricular tachycardia?

Ventricular tachycardia happens when some of the cells in your ventricle start acting like pacemaker cells. If they go faster than your normal pacemaker cells, they can take over your heart and make it beat very fast.

Sustained ventricular tachycardia usually happens in older people with heart problems, such as a:

Other causes may include:

What are the symptoms of ventricular tachycardia?

Symptoms of ventricular tachycardia include:

  • Palpitations

  • Feeling weak and light headed

  • Chest discomfort

What are the complications of ventricular tachycardia?

Sustained ventricular tachycardia can cause more dangerous problems, such as:

How can doctors tell if I have ventricular tachycardia?

Doctors feel your pulse and do:

An ECG is a quick, painless test that measures your heart’s electrical activity using stickers and cables on your chest, arms, and legs.

If the ECG shows ventricular tachycardia, doctors usually do:

  • Blood tests to check for abnormal electrolyte levels and signs of heart damage

How do doctors treat ventricular tachycardia?

Doctors only need to treat ventricular tachycardia if:

  • You have symptoms

  • You have sustained ventricular tachycardia

Right away, doctors treat it with:

  • Cardioversion

In cardioversion, doctors give a short electrical shock to your heart. They give the shock through sticky pads on your chest or sometimes paddles they hold against your chest. The shock stops the tachycardia so your heart can resume its normal rhythm. You may need several shocks. Doctors will give you medicine directly into your vein (IV medicine) so you're sleepy and it doesn't hurt.

Certain IV medicines can sometimes stop the tachycardia, but doctors usually prefer cardioversion because it's quicker and safer.

If you keep having ventricular tachycardia, you may need:

  • An implantable cardioverter-defibrillator (ICD)

An ICD is a device implanted under the skin of your chest or stomach. The device is connected to your heart with wires so it can monitor your heart beat. It can automatically give you a shock and restart your heart if you have ventricular tachycardia or ventricular fibrillation.

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