What is bradycardia?

Definition
Bradycardia is defined as a slow or irregular heart rhythm. Brady means slow and Cardia means heart. A healthy heart beats 60 to 100 times per minute, pumping about 75 gallons of blood every hour.

When you have bradycardia, the heart beats fewer than 60 times per minute. At this rate, the heart is not able to pump enough oxygen-rich blood to your body during normal activity or during periods of exercise. As a result you might feel dizzy, short of breath, or have fainting spells.

Causes
Bradycardia can occur for several reasons. Common causes of bradycardia include:

  • Congenital heart disease (i.e., condition you were born with)
  • Certain illnesses of heart medications
  • The natural aging process
  • Scar tissue from a heart attack
  • Sick sinus syndrome, also called sinus node dysfunction (the heart’s natural pacemaker not functioning correctly)
  • Heart block (the electrical impulse that travels from the upper to the lower chamber of the heart is irregular or blocked)

Symptoms
When your heart beats too slowly you may experience various symptoms. These symptoms including dizziness, fainting, chronic lack of energy, and shortness of breath, help your doctor access the severity of your heart condition and determine the appropriate treatment for you.

Symptoms of bradycardia

Risk Factors
Your risk of developing an abnormally slow heart rate (bradycardia) is greater if you:

  • Have certain types of heart disease
  • Are taking certain medicines
  • Are age 65 or older
  • Have recently had heart surgery