Ventricular tachycardia (V tach)

A fast heart rate that starts in the lower parts of the heart (ventricles) is called ventricular tachycardia (V tach). Ventricular tachycardia is a medical emergency.

The lower chambers of the heart (ventricles) pump blood to every organ in the body, including the heart itself. The ventricles receive blood from the upper chambers of the heart (atria). When the heart is beating normally, blood flows into the ventricles when the atria contract.

When the ventricles are beating very rapidly, there is little time for the ventricles to fill with blood from the atria and also little time to effectively pump that blood out to the rest of the body. Because of the reduced blood flow to the body, a person with ventricular tachycardia will usually have some or all of the following symptoms:

• Low blood pressure
• Dizziness or lightheadedness
• Shortness of breath
• Loss of consciousness
• Weak or absent pulse

While a few people with ventricular tachycardia will have minimal symptoms, this heart rhythm is considered a medical emergency and must be treated immediately. Untreated ventricular tachycardia can often worsen and lead to ventricular fibrillation and death.

Paramedics are trained to identify and immediately treat ventricular tachycardia in the field. Likewise, airline employees are taught to use an automatic defibrillator for this emergency.

Treatment for ventricular tachycardia consists of:

• Medications given by medical personnel through a vein (intravenous, or IV).
• An electrical shock to the heart (cardioversion).

If another episode of ventricular tachycardia is likely, an implantable cardioverter-defibrillator (ICD) may need to be surgically placed in the chest. An ICD is a small device that can tell whether the heart is in ventricular tachycardia and can deliver a small electrical shock to the heart when the tachycardia occurs.