Pronounced: Bray-dee-car-dee-uhEn Español (Spanish Version)
Bradycardia is an abnormally slow heart rate. In adults, it is defined as a heart rate of less than 60 beats per minute. Different types of bradycardia are collectively referred to as bradyarrhythmias. They include:
- Sinus bradycardia—an unusually slow heartbeat due to heart disease, a reaction to medication, or harmless causes, such as excellent fitness or deep relaxation
- Sick sinus syndrome—an unusually slow heartbeat due to a malfunction of the sinoatrial node, which is the heart's natural pacemaker
- Heart block (atrioventricular block or AV block)—an unusually slow heartbeat due to a slowing or blocking of electrical impulses in the heart’s conduction system
Heartbeat: Anatomy of the Heart
Copyright © Nucleus Medical Media, Inc.
Last reviewedDecember 2013by Michael J. Fucci, DO
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.