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by Scholten A


(Ventricular Tachycardia; Supraventricular Tachycardia; Paroxysmal Atrial Tachycardia)


Tachycardia is a fast heartbeat. It is a rate of more than 100 beats per minute.
It is normal for the heart to beat faster with exercise or stress. However, some fast heart beats are abnormal. They are called arrhythmias. Some arrhythmias can be life-threatening. They need to be treated.
Electrical System and Chambers of the Heart
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Signals in the heart control how the heart beats. Tachycardia is caused by abnormal signals.

Risk Factors

Things that raise the risk of tachycardia are:
  • Heart problems, such as:
  • Electrolyte problems—too much or too little calcium, sodium, magnesium, and potassium in the blood
  • Hypoxemia—not enough oxygen in the blood
  • Acidosis—too much acid in the body’s fluids


Symptoms of tachycardia are:
  • Pounding heartbeats
  • Fast heartbeats
  • Lightheadedness or fainting
  • Chest pain
  • Problems breathing


Your doctor will ask about symptoms and past health. A physical exam will be done.
Tachycardia is usually diagnosed with an electrocardiogram (ECG). Patches are placed on the chest, arms, and legs—to check heart activity.
Other tests may be:


The goal is to slow the fast heartbeats and prevent them from happening again. This includes treating any conditions that are causing the fast heartbeats.
Fast heartbeats that are life-threatening need care right away.
Care options may be:
Device to Correct Tachycardia
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The risk of tachycardia may be lowered by:


American Heart Association
Heart Rhythm Society


Canadian Heart Rhythm Society
Heart and Stroke Foundation of Canada


Arrhythmias. American Heart Association website. Available at: https://www.heart.org/en/health-topics/arrhythmia. Accessed September 10, 2021.
Cardioversion of atrial fibrillation. EBSCO DynaMed website. Available at: https://www.dynamed.com/procedure/cardioversion-of-atrial-fibrillation. Accessed September 10, 2021.
Implantable cardioverter defibrillator (ICD). EBSCO DynaMed website. Available at: https://www.dynamed.com/device/implantable-cardioverter-defibrillator-icd-16. Accessed September 10, 2021.
Littmann L, Olson EG, et al. Initial evaluation and management of wide-complex tachycardia: a simplified and practical approach. Am J Emerg Med. 2019;37(7):1340-1345.
Risk factors & prevention. Heart Rhythm Society website. Available at: https://upbeat.org/early-warning-signs#axzz3NOr35s6f. Accessed September 10, 2021.
Supraventricular tachycardia (SVT). EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/supraventricular-tachycardia-svt. Accessed September 10, 2021.
Tachyarryhthmias. EBSCO DynaMed website. Available at: https://www.dynamed.com/approach-to/tachyarrhythmias-approach-to-the-patient. Accessed September 10, 2021.
Ventricular tachycardia—approach to the patient. EBSCO DynaMed website. Available at: https://www.dynamed.com/approach-to/ventricular-tachycardia-approach-to-the-patient. Accessed September 10, 2021.

Revision Information

  • Reviewer: EBSCO Medical Review Board Nicole Meregian, PA
  • Review Date: 07/2021
  • Update Date: 09/10/2021