Ventricular Tachycardia

Overview

Definition

Ventricular tachycardia is an abnormally fast heart rate. The abnormal heart rate originates in one of the heart's lower chambers (ventricles). It is diagnosed when there are 3 or more beats in succession originating from a ventricle. The heart beats at a rate greater than 100 beats per minute, but fewer than 200 beats per minute.

Ventricular tachycardia is considered sustained if it lasts more than 30 seconds. When this condition is sustained, the ventricles are not able to fill with enough blood for the heart to keep blood flowing properly through the body. This can result in lowered blood pressure, heart failure, and death.

Heart Chambers and Valves
heart anatomy
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Causes

Damage to the ventricles can cause ventricular tachycardia. This damage to the heart muscle may be due to conditions like a heart attack or cardiomyopathy.

Risk Factors

Factors that may increase your chances of ventricular tachycardia:

  • Coronary artery disease (CAD)
  • History of heart attacks
  • Heart abnormalities, such as cardiomyopathy, mitral valve prolapse, valvular heart disease, or ion channel disorders
  • Diagnosis of electrical instability
  • Sarcoidosis
  • Beginning treatment for hypothyroidism
  • Use of certain medications, such as antipsychotics or anti-arrhythmic drugs
  • Extreme physical or emotional overstimulation
  • Low oxygen levels in the blood
  • Very high levels of acid in bodily fluids
  • Excessive alcohol use
  • Stimulants, such as caffeine or cocaine
Coronary Artery Disease
Coronary Artery plaque
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SymptomsandDiagnosis

Symptoms

Ventricular tachycardia may cause:

  • A sensation of the heart beating very rapidly—palpitations
  • Feeling lightheaded
  • Feeling short of breath
  • Fainting
  • Chest discomfort
  • Pale skin color

Diagnosis

This condition can be challenging to diagnose. Ventricular tachycardia often happens in emergency situations. It must be identified and treated very quickly.

To make the diagnosis, the doctor will order tests, such as:

  • ECG to test the electrical activity of the heart
  • Exercise stress test to test the heart’s performance
  • Electrophysiology test to study the electrical signals of the heart

Treatments

Treatment

In an emergency situation, CPR or a defibrillator may be required.

Other treatment options may include:

  • Medications to manage high blood pressure or heart rate
  • Surgery, such as:
    • Radiofrequency ablation
    • Open heart surgery

If other approaches fail, an automatic defibrillator will be inserted into the heart to deliver shocks as needed to keep the heart rate steady.

Prevention

To help reduce your chances of ventricular tachycardia:

  • Take medications to control heart rate and blood pressure.
  • Get proper treatment for any underlying heart conditions.
  • Use alcohol and caffeine in moderation.
  • Take prevention steps to avoid heart disease by maintaining a healthy weight and exercising.
  • If you smoke, talk to your doctor about how you can successfully quit.

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Edits to original content made by Denver Health.

RESOURCES

American Heart Association http://www.heart.org 

Heart Rhythm Society http://www.hrsonline.org 

CANADIAN RESOURCES

Canadian Heart Rhythm Society http://www.chrsonline.ca 

Heart and Stroke Foundation of Canada http://www.heartandstroke.ca 

References

Ventricular tachycardia. EBSCO DynaMed Plus website. Available at:  http://www.dynamed.com/topics/dmp~AN~T115268/Ventricular-tachycardia . Updated January 26, 2016. Accessed November 29, 2017.

Ventricular tachycardia (VT). Merck Manual Professional Version website. Available at: http://www.merckmanuals.com/professional/cardiovascular%5Fdisorders/arrhythmias%5Fand%5Fconduction%5Fdisorders/ventricular%5Ftachycardia%5Fvt. Updated September 2017. Accessed November 29, 2017.

Ventricular tachycardia (VT). New York-Presbyterian Hospital website. Available at: http://www.nyp.org/library/134%257C231?l=en. Accessed November 29, 2017.