Arrhythmias are caused by a change in the electrical signals of the heart. It may be an abnormal signal or a problem with how the signal moves through the heart. This may happen because of one or more of the following:

The heart's pacemaker (sinoatrial [SA] node) is not working as it should. It will set a rate or rhythm that isn’t normal.
Damage to the heart that makes it harder for these signals to move through the heart. May be caused by injury or illness such as:
- Coronary artery disease
- Heart muscle damage—cardiomyopathy
- Problems with your heart valves
- Direct trauma to your heart
- Heart problems you’ve had since birth
A signal to contract starts in areas of the heart other than the SA node.
Problems with how your muscles and nerves work.

Factors outside the body that can affect the rhythm of the heart include:

Stress
Caffeine
Tobacco
Alcohol
Illegal drugs such as cocaine and amphetamines
Diet pills
Certain medicines, such as those used to treat a cough or cold, heart problems, asthma, depression, or thyroid problems.

References:

Arrhythmia. National Heart, Lung, and Blood Institute website. Available at: https://www.nhlbi.nih.gov/health-topics/arrhythmia. Accessed January 2, 2019.

Atrial fibrillation. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T115288/Atrial-fibrillation. Updated August 22, 2018. Accessed January 2, 2019.

Atrial flutter. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T115251/Atrial-flutter. Updated February 22, 2017. Accessed January 2, 2019.

Atrioventricular (AV) conduction disorders. EBSCO DynaMed Plus website. Available at: http://www.dynamed.... Updated November 27, 2017. Accessed January 2, 2019.

Symptoms, diagnosis and monitoring of arrhythmia. American Heart Association website. Available at: https://www.heart.org/en/health-topics/arrhythmia/symptoms-diagnosis--monitoring-of-arrhythmia. Accessed January 2, 2019.

Understand your risk for arrhythmia. American Heart Association website. Available at: https://www.heart.org/en/health-topics/arrhythmia/understand-your-risk-for-arrhythmia#.WTAaIOvytQJ. Accessed January 2, 2019.

Ventricular arrhythmias. EBSCO DynaMed Plus website. Available at: http://www.dynamed.... Updated October 19, 2018. Accessed January 2, 2019.

Last reviewed December 2018 by EBSCO Medical Review Board Michael J. Fucci, DO, FACC
Last Updated: 1/2/2019

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