atrial fibrillation

American  

[ey-tree-uhl fib-ruh-ley-shuhn] / ˈeɪ tri əl ˌfɪb rəˈleɪ ʃən /

noun

Pathology.

1. a cardiac arrhythmia, or irregular heartbeat, caused by rapid, chaotic electrical impulses to the atria. AF, AFib.

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Etymology

Origin of atrial fibrillation

First recorded in 1905–10

Example Sentences

Researchers expect increases across every major category of cardiovascular disease in women, including heart disease, heart failure, atrial fibrillation and stroke.

From Science Daily • Feb. 27, 2026

The positive result came after Bayer stopped a trial of the same drug to prevent stroke in patients with atrial fibrillation two years ago, because an existing treatment called apixaban performed better.

From MarketWatch • Nov. 24, 2025

The anticoagulant drugs and cardiac ablation procedures for treating atrial fibrillation aren’t without complication, so large studies are trying to determine if the additional arrhythmias found by devices like Zio are truly stroke threats.

From Barron's • Nov. 5, 2025

Patients with atrial fibrillation can now monitor their heart rhythm with a do-it-yourself electrocardiogram on devices that interface with a smartphone app and range from $79 to $129.

From The Wall Street Journal • Sep. 30, 2025

They said that includes a recent fainting episode, and over the last five years, a broken back, a torn Achilles tendon and atrial fibrillation which could make Murdoch “unavailable for in-person testimony at trial.”

From Los Angeles Times • Aug. 5, 2025