Bradycardia is a type of heart rhythm disorder. It happens when someone's heart rate falls below 50 beats per minute, which is slower than normal.
The heart's electrical system controls when the heart contracts and pumps blood out to the body. If you have bradycardia, these signals are sluggish, or they become blocked in some way.
Bradycardia can be caused by:
In some instances, a slow heart rate is normal. For example, being very athletic and physically fit can lead to the heart pumping more efficiently so it doesn't need to beat as many times a minute to meet the body's needs. Your heart also tends to naturally beat more slowly during sleep.