What Is Tachycardia and What Causes It?

 

Definition

Tachycardia is a common type of heart rhythm disorder (arrhythmia) in which the heart beats faster than normal in the upper or lower chambers of the heart or both while at rest.

Electrical signals sent across heart tissues control your heart rate. Tachycardia occurs when an abnormality in the heart produces rapid electrical signals that quicken the heart rate, which is normally about 60 to 100 beats a minute at rest.

There are many different types of abnormal tachycardia such as:

  • Atrial fibrillation. It is a rapid heart rate caused by chaotic, irregular electrical impulses in the upper chambers of the heart (atria). It is the most common type of tachycardia.
  • Atrial flutter. This makes the heart’s atria beat very fast but at a regular rate. It is caused by irregular circuitry within the atria.
  • Supraventricular tachycardia (SVT). It is an abnormally fast heartbeat that originates somewhere above the ventricles. It’s caused by abnormal circuitry in the heart that is usually present at birth and creates a loop of overlapping signals.
  • Ventricular tachycardia. It is a rapid heart rate that originates with abnormal electrical signals in the lower chambers of the heart (ventricles). The rapid heart rate doesn’t allow the ventricles to fill and contract efficiently to pump enough blood to the body.
  • Ventricular fibrillation. It occurs when rapid, chaotic electrical impulses cause the ventricles to quiver ineffectively instead of pumping necessary blood to the body.

Causes

The causes of tachycardia include:

  • Damage to heart tissues from heart disease
  • Abnormal electrical pathways in the heart present at birth
  • Disease or congenital abnormality of the heart
  • Anemia
  • Exercise
  • Sudden stress, such as fright
  • High or low blood pressure
  • Smoking
  • Fever
  • Drinking too much alcohol or too many caffeinated beverages
  • Medication side effects
  • Abuse of recreational drugs, such as cocaine
  • Imbalance of electrolytes, mineral-related substances necessary for conducting electrical impulses
  • Overactive thyroid (hyperthyroidism)
* The Content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.