atrial fibrillation

noun

Medical Definition of atrial fibrillation

: very rapid uncoordinated contractions of the atria of the heart resulting in a lack of synchronism between heartbeat and pulse beat If you're experiencing chest pain, palpitations, lightheadedness or shortness of breath, you could have atrial fibrillation (AF), a condition in which the heart's upper chambers (atria) "quiver."— Abigail L. Cuffey, Woman's Day abbreviation AF

called also A-fib, auricular fibrillation

Learn More About atrial fibrillation

Dictionary Entries Near atrial fibrillation

atrial

atrial fibrillation

atrial flutter

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Cite this Entry

“Atrial fibrillation.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/atrial%20fibrillation. Accessed 26 May. 2022.

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