arrhythmia

American  

[uh-rith-mee-uh, ey-rith-] / əˈrɪð mi ə, eɪˈrɪð- /

noun

Pathology.

1. any disturbance in the rhythm of the heartbeat.

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arrhythmia British  

/ əˈrɪðmɪə /

noun

1. any variation from the normal rhythm in the heartbeat

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arrhythmia Scientific  

/ ə-rĭth′mē-ə /

1. An abnormal rhythm of the heart, often detectable on an electrocardiogram. Electrical impulses in the heart normally originate in the sinoatrial node of the right atrium during diastole and are transmitted through the atrioventricular node to the ventricles, causing the muscle contraction that usually occurs during systole. However, abnormalities of electrical conduction during diastole or systole can result in various alterations of the heartbeat, such as changes in heart rate, skipped or irregular beats, and fibrillation of the heart muscle, which can be life threatening. These electrical disturbances can be caused by metabolic abnormalities, inadequate blood supply (as in coronary artery disease), drug effects, chronic disease, and other factors. Arrhythmias are sometimes treated with the implantation of a pacemaker.

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Other Word Forms

• arrhythmic adjective
• arrhythmical adjective
• arrhythmically adverb

Etymology

Origin of arrhythmia

1885–90; < New Latin < Greek arrhythmía. See a- ⁶, rhythm, -ia

Compare meaning

How does arrhythmia compare to similar and commonly confused words? Explore the most common comparisons:

• arrhythmia vs. dysrhythmia

Example Sentences

The suspected cardiac arrhythmia was likely due to a diagnosed condition known as “systemic sarcoidosis,” which can cause lumps in the lungs and other organs, the report found.

From Los Angeles Times • Jan. 22, 2026

And in 1987, a heart arrhythmia caused Soviet cosmonaut Aleksandr Laveykin to leave the Mir space station early.

From BBC • Jan. 14, 2026

Cardiomyocytes as the main actors in arrhythmia are very well studied, but if and how immune cells can promote arrythmia is less clear.

From Science Daily • Oct. 13, 2025

Ferrari’s report disputed the severity of that episode, contending the arrhythmia could not have triggered agony for more than “a few minutes or at most a few hours.”

From Seattle Times • Apr. 29, 2024

I don’t know what an arrhythmia is, and I can’t bring myself to ask.

From "I Can Make This Promise" by Christine Day