Ventricular Tachycardia

Ventricular tachycardia is a type of arrhythmia that originates in the ventricles, the heart’s lower chambers. Characterized by a rapid rhythm (defined as a pulse rate of more than 100 beats per minute) and at least three consecutive abnormal heartbeats, ventricular tachycardia occurs when electrical signals from the ventricles misfire and disrupt the work of the sinoatrial node, a structure that helps keep the heart in rhythm. This process speeds the heart rate and prevents blood from filling the heart during beats, which affects blood flow throughout the body. In some cases, ventricular tachycardia is life-threatening.

Symptoms

Not all cases of ventricular tachycardia involve symptoms, but this condition can cause:

  • A fast or irregular heartbeat
  • A weak or undetectable pulse
  • Cardiac arrest
  • Chest pain
  • Difficulty breathing
  • Dizziness
  • Fainting

Prevention

It’s not always possible to prevent ventricular tachycardia, but you may be able to reduce your risk by making healthy lifestyle changes that can help you avoid a heart attack, which is a risk factor for this condition. You may also be able to lower your risk of ventricular tachycardia by treating or managing cardiac conditions that can contribute to it.

Risk Factors

  • Cardiac surgery
  • Certain drugs that prevent arrhythmia
  • Congenital heart disease
  • Heart attack
  • Heart failure
  • Heart valve disease
  • Inflammation of the heart muscle
  • Low blood potassium
  • Poor blood flow to the heart
  • Thickening or enlargement of the heart muscle

Diagnosis

  • Medical history. Be prepared to tell your cardiologist about your medical history, any medications you take and any symptoms you have experienced.
  • Physical exam. As part of this exam, your cardiologist will listen to your heart and check your pulse for indicators of ventricular tachycardia.
  • Blood tests. These tests can provide a wealth of information about your health, including your potassium level.
  • Chest X-ray. This imaging test can show whether the heart is enlarged.
  • Electrocardiogram. Also known as an EKG or ECG, this test allows your cardiologist to see how your heart’s electrical system is functioning. It can detect an episode of ventricular tachycardia if one occurs during the test.
  • Holter monitor. Your cardiologist may ask you to wear this device for up to 48 hours so it can record your heart rhythm and, possibly, detect ventricular tachycardia.
  • Electrophysiology study. During this test, a cardiologist uses catheters to send electrodes to the heart to gauge its electrical activity or stimulate an arrhythmia to uncover its origin. 

Treatment

  • Severe, extended episodes of ventricular tachycardia can be dangerous and require CPR and an electric shock with an external defibrillator, which can help the heart get into a normal rhythm.
  • If ventricular tachycardia does not cause distress and pose an imminent threat to life, your cardiologist may recommend an antiarrhythmic medication to prevent future episodes.
  • Another treatment option your cardiologist may recommend is radiofrequency ablation, a catheter-based procedure that uses electrodes to locate the source of ventricular tachycardia and deliver heat energy to destroy the tissue that’s responsible for it.
  • You may be a candidate for an implantable cardioverter defibrillator (ICD), a small device that is placed in your chest. This device can detect ventricular tachycardia when it occurs and provide an electric shock to send the heart into a normal rhythm.

Follow-up Care

  • Be sure to follow your cardiologist’s instructions for treatment and notify him or her if you experience any new symptoms. If you undergo radiofrequency ablation, you may experience fatigue, chest soreness or an occasional skipped heartbeat for a few days after the procedure.
  • If you undergo ICD implantation, you may take up to six weeks to fully recover and may be restricted from performing certain movements, such as lifting your arm above your shoulder.
  • Keep all follow-up appointments with your cardiologist for long-term monitoring.