About the Heart Rate

• The heart rate is controlled by electrical impulses sent across the heart tissue with each beat. A racing heart beat occurs when abnormalities cause these impulses to be sent too quickly.
  
  

Types

• There are several common types of tachycardia. Atrial fibrillation or flutter affects the heart atria, ventricular tachycardia or fibrillation affects the heart ventricles, and supraventricular tachycardia occurs above the ventricles.
  
  

External Causes

• Illicit drug use, especially cocaine, excessive alcohol consumption, smoking, drinking too much caffeine and certain over-the counter medications including nasal decongestants can all cause a racing heart beat.
  
  

Medical Conditions

• Heart disease, a history of heart attack and structural abnormalities can cause tachycardia. Previous trauma, including being struck by lightning, can also have a long-term effect on heart rate.
  
  

Emotional Causes

• Tachycardia can also be brought on by emotional issues such as stress, anxiety and feelings of panic. People who become easily excited or overwhelmed are likely to experience temporary tachycardia.