A frequent rhythm disturbance (most frequent in elderly patients) originating from the atria and resulting in ineffective atrial contractions. It can result in rapid heart rhythm.
Due to the ineffective contraction of the atria, cardiac output is reduced and this can be clinically manifested by congestive heart failure, especially in patients with a significant background heart disease.
In addition, Atrial Fibrillation harbors an increased risk of formation of thrombi in the heart.
For this reason, people with chronic or frequent paroxysmal Atrial Fibrillation are often treated with drugs preventing thrombus formation, such as Coumadin.
Atrial fibrillation can be reverted by drugs or by electrical shock (Cardioversion).