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atrial fibrillation

American  
[ay-tree-uhl fib-ruh-lay-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.


Etymology

Origin of atrial fibrillation

First recorded in 1905–10

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Doctors are changing their referral practices for the Watchman device because there has been a lot of evidence published in recent months about the risk of stroke for people with atrial fibrillation, Mahoney said.

From The Wall Street Journal ● Jul. 29, 2026

The new statement reviews recent evidence about caffeinated coffee and its possible relationships with high blood pressure, cholesterol, Type 2 diabetes, coronary heart disease, stroke, heart failure, atrial fibrillation, other arrhythmias and other cardiovascular conditions.

From Science Daily ● Jul. 22, 2026

According to Civello, the next wave — in which wearables can detect conditions like atrial fibrillation, hypertension and sleep apnea — is happening now.

From MarketWatch ● May 28, 2026

It’s a common alternative for patients with atrial fibrillation who can’t take long-term blood thinners.

From Barron's ● May 27, 2026

Women experiencing heart attacks, heart failure, atrial fibrillation or stroke require timely and high quality treatment.

From Science Daily ● Feb. 27, 2026

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