Health Encyclopedia
Search Clinical Content Search Patient Health Library
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A-Z Listings

Bradycardia

Cross section of heart showing left atrium and SA node and AV node in right atrium.

A slow heart rate is less than 60 beats a minute. That is called bradycardia. Bradycardia can be normal. Or it can be caused by medicines. Or it can be a sign of a disease. The slow heart rate may not be constant. It can come and go. It's a concern when it is very low, or when you have symptoms.

Symptoms

Symptoms of bradycardia are:

  • Dizziness or feeling lightheaded.

  • Weakness.

  • Trouble breathing.

  • Fainting.

  • Sleepiness.

  • More trouble exercising than normal because of tiredness (fatigue).

  • Confusion or trouble concentrating.

Causes

Bradycardia can have many causes. Some can be linked to your heart. But some may be linked to other things.

Nonheart-related causes:

  • Being older.

  • A side effect of certain medicines. These include beta-blockers, calcium channel blockers, digitalis, clonidine, lithium, and medicines to treat arrhythmias, such as amiodarone.

  • Health conditions, like low thyroid (hypothyroidism) and electrolyte disorder. Other examples are low body temperature (hypothermia) and sleep apnea.

  • Athletes, especially long-distance runners, may have a slow heart rate. This can be normal.

  • Brain injury, such as stroke or bleeding inside the brain.

Heart-related causes:

  • Coronary artery disease. This includes angina or past heart attack (acute myocardial infarction).

  • Heart valve disease.

  • Heart muscle disease (cardiomyopathy).

  • Congestive heart failure.

  • Sick sinus syndrome. This is when your heart's natural pacemaker is no longer working correctly.

  • Heart block. This is when your heart's natural electrical pathways no longer work correctly.

  • Diseases that enter the heart, such as sarcoid.

  • Heart infections.

Sometimes the cause for the arrhythmia can't be found.

Bradycardia that causes symptoms is sometimes reversible. When more severe bradycardia continues, you may need a pacemaker. Bradycardia may not cause symptoms. In this case, your health care provider may decide to watch it over time.

Home care

You can care for yourself at home:

  • Go back to your normal activities when you are feeling back to normal.

  • If you have any of the symptoms of bradycardia when you exert yourself, stop. Don't exert yourself. Wait until you have seen your health care provider for an assessment.

  • Work with your provider on any lifestyle changes you need. These might mean changing your diet, stopping smoking if you are a smoker, and starting an exercise program.

Follow-up care

Follow up with your health care provider as advised.

Call 911

Call 911 right away if:

  • You have chest pain.

  • You have chest pain that spreads to the shoulder, arm, neck, or back.

  • You have trouble breathing.

  • You have a slow heart rate with dizziness or lightheadedness.

  • You fainted or lost consciousness.

When to get medical care

Contact your health care provider if:

  • You have occasional weakness.

  • You feel dizzy or lightheaded.

  • You have abnormal trouble exercising.

Online Medical Reviewer: Stacey Wojcik MBA BSN RN
Online Medical Reviewer: Steven Kang MD
Date Last Reviewed: 1/1/2025
© 2000-2025 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.
Powered by Krames by WebMD Ignite

These resources and their content are provided by a third party for informational purposes and do not necessarily reflect the values and positions of Ascension, its ministries, or its subsidiaries.

About StayWell | Terms of Use | Privacy Policy | Disclaimer

The Services may integrate with Third-Party Apps or contain third-party content or provide links to third-party websites. For example, the Services may integrate with Third-Party App providers to provide you with information. You authorize Ascension to transmit information about You to and receive information about You from applicable third parties.
You agree that Ascension is not responsible for Third-Party Apps, third-party content or third-party websites, and does not make any endorsements, representations or warranties regarding the same. Your use thereof is at Your own risk and subject to the third party’s terms and conditions, as applicable. By using a Third-Party App or third-party content or websites, You agree to the applicable third party’s terms and conditions, even if Ascension does not present them to You at the time of Your use.