©2018 WebMD, Inc. All rights reserved. eMedicineHealth does not provide medical advice, diagnosis or treatment. See Additional Information.

Symptoms and Signs of Atrial Fibrillation (AFib)

Doctor's Notes on Atrial Fibrillation (AFib)

Atrial fibrillation is an irregular heart rhythm (arrhythmia) that is irregular, often rapid heart rhythm that causes the atrial chambers of the heart to beat rapidly. Signs and symptoms of atrial fibrillation (also termed A fib, AFib, A-fib) may include

The cause of atrial fibrillation is due to multiple sources of impulses in the atria that travel through the atria at the same time and cause irregular usually rapid contractions of the atria that are not correlated with ventricular contractions although ventricular contractions are also frequently increased. Other cardiac conditions may eventually cause atrial fibrillation. For example, heart valve disease, ventricular hypertrophy, coronary heart disease, congestive heart failure, advancing age and others.

Other causes that may trigger atrial fibrillation symptoms, for example, are overactive thyroid, alcohol use, pulmonary embolism and pneumonia.

Medical Author:
Medically Reviewed on 5/8/2020

Atrial Fibrillation (A-Fib) : Test Your Medical IQ Quiz

Atrial Fibrillation Quiz

Atrial fibrillation is a(n) ...

See Answer


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.