Atrial fibrillation
Most common serious abnormal heart rhythm, affecting over 33 million people.
Atrial fibrillation (AF, AFib or A-fib) is an abnormal heart rhythm (arrhythmia) characterized by rapid and irregular beating of the atrial chambers of the heart. It often begins as short periods of abnormal beating, which become longer or continuous over time. It is the most common serious abnormal heart rhythm and, as of 2020, affects more than 33 million people worldwide.
- global_prevalence_2020
- over 33 million
- prevalence_in_Europe_and_North_America_2
- 2 to 3%
- percentage_under_50_years
- 0.1%
- percentage_60_to_70_years
- 4%
- percentage_over_80_years
- 14%
Lore & Background
Atrial fibrillation is a supraventricular tachycardia that frequently results from bursts of tachycardia originating in muscle bundles extending from the atrium to the pulmonary veins. The ganglionated plexi, left atrial appendage, and ligament of Marshall can also be sources. As AF becomes more persistent, the left atrium itself becomes an independent source of arrhythmias. High blood pressure and valvular heart disease are the most common modifiable risk factors; other risks include heart failure, coronary artery disease, COPD, obesity, sleep apnea, excess alcohol, tobacco, diabetes, and thyroid disorders. About half of cases are not associated with any of these risks.
Reader's Guide
Atrial fibrillation is significant as the most common serious arrhythmia, with increasing incidence and prevalence worldwide. It is associated with elevated risks of heart failure, dementia, and stroke. Diagnosis is confirmed by ECG showing irregularly spaced QRS complexes without P waves. Treatment includes rate control, rhythm control, electrical cardioversion, and ablation. Anti-clotting medications reduce stroke risk but increase major bleeding. Healthy lifestyle changes—weight loss, physical activity, reduced alcohol—can lower risk and burden.
Did You Know?
- Atrial fibrillation often begins as short periods of abnormal beating that become longer or continuous over time.
- It may start as other arrhythmias such as atrial flutter that transform into AF.
- Pulmonary vein isolation by transcatheter ablation can restore sinus rhythm.
Frequently Asked Questions
Who is Atrial fibrillation?
Atrial fibrillation (AFib) is the most common serious arrhythmia, defined by fast, disorganized contractions of the heart's upper chambers. It is not a single dramatic event but a chronic rhythm disorder that has now affected more than 33 million people worldwide as of 2020.
What are Atrial fibrillation's powers/role?
AFib hijacks the normal electrical sequence in the atria, replacing coordinated beats with chaotic, rapid quivering that disrupts efficient blood flow. Episodes often begin as brief, self-resolving bouts before stretching into longer or fully continuous runs over time.
How does Atrial fibrillation's story end?
There is no clean 'ending' in the traditional sense; AFib typically transitions from paroxysmal to persistent and eventually permanent rhythm disruption. Long-term management therefore centers on controlling heart rate, restoring sinus rhythm when possible, and reducing the elevated stroke risk it creates.
Why is Atrial fibrillation important?
Its sheer scale makes it a dominant storyline in cardiovascular medicine: prevalence climbs from roughly 0.1% in people under 50 to about 14% in those over 80. With 2–3% of adults in Europe and North America affected, it drives enormous clinical and public-health attention.
Who does Atrial fibrillation target?
AFib is heavily age-weighted, striking only a tiny fraction of younger adults but a large share of the elderly. Its global footprint spans all regions, yet the highest per-capita burdens are concentrated in older populations across Europe, North America, and increasingly in aging societies worldwide.
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