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
light-headedness
- 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.