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Ventricular Tachycardia

Topic Overview

If you have supraventricular tachycardia (SVT), go to the topic Supraventricular Tachycardia.

What is ventricular tachycardia?



What causes ventricular tachycardia?




What are the symptoms?


Symptoms include:


How is ventricular tachycardia diagnosed?

If an electrocardiogram (EKG, ECG) can be performed while ventricular tachycardia is occurring, it often provides the most useful information. An electrocardiogram is a tracing of the electrical activity of your heart. It is usually done along with a history and physical examination, lab tests, and a chest X-ray.


Your doctor may recommend further tests, including an echocardiogram, to evaluate your heart's function, a stress test or coronary angiogram to determine whether a part of the heart is not getting enough blood, and/or an electrophysiology study. During an electrophysiology (EP) study, electrical currents are sent through a catheter into the heart to try to trigger ventricular tachycardia and record the flow of electricity through the heart. In this way, the EP study can locate specific areas of heart tissue that give rise to abnormal electrical impulses, which may be causing the ventricular tachycardia. This information is used to determine the best treatment.

How is it treated?

If you are having symptoms and are in a sustained tachycardia, it is a medical emergency. You will require immediate treatment. You may need CPR or a shock from an automatic defibrillator (also known as an AED). Paramedics or your doctor may try intravenous medicines or electrical cardioversion to return your heart to a normal rhythm.

To prevent the arrhythmia from recurring, you may need to take antiarrhythmic medicines. But these medicines may have side effects. So instead, doctors often recommend a type of permanent pacemaker, called an implantable cardioverter defibrillator (ICD). This device is placed under the skin in your chest and continuously monitors your heart's rhythm. If ventricular tachycardia occurs, the ICD applies an electrical shock to the heart to restore a normal rhythm. After a normal rhythm is restored, the device goes back to continuous monitoring mode. Sometimes, both medicines and an ICD are needed.

Click here to view a Decision Point.Heart Rate Problems: Should I Get an ICD?

In some cases a procedure called catheter ablation is used to destroy small areas of heart tissue responsible for the arrhythmia. In this procedure, thin, flexible wires are inserted into a blood vessel in the thigh, groin, neck, or elbow and threaded to the heart. Through these wires, heat or freezing cold temperatures can be delivered to the specific heart tissue that is generating abnormal electrical impulses (previously located in the EP study). The heat or freezing cold destroy (ablate) this heart tissue and can stop ventricular tachycardia from happening again.


What precautions should you take?



When to call a doctor

If you have palpitations, dizziness, near-fainting, or chest pain, call or other emergency services immediately.

If you have an ICD

If you have an ICD, be sure you have a plan for what to do if you get a shock. Talk to your doctor if you need to make a plan. In general, your plan depends on how you feel after you get a shock and how many times you get a shock.

After one shock:

  • Callor other emergency services immediately if you feel bad or have symptoms like chest pain.
  • Call your doctor soon if you feel fine right way. Your doctor may want to talk about the shock and schedule a follow-up visit.

After a second shock within 24 hours:

  • Call your doctor immediately, even if you feel fine right away.

eMedicineHealth Medical Reference from Healthwise


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