What causes atrial fib?

Atrial fibrillation: The two most common causes of atrial fibrillation are hyperthyroidism (overactive thyroid) and degenerative disease of the cardiac conduction system as we get older. Other causes include heart surgery, alcohol (chronic intoxication), and conditions which enlarge the atria (like heart valve problems).

Many causes: There are many factors that can lead to atrial fibrillation. Common predisposing conditions include hypertension, heart failure, sleep apnea, and genetic predisposition.

Many causes: Most of the time however the cause is not clear. Electrical conductive disease, thyroid disease, coronary artery disease, cardiomyopathy, alcohol, drugs like amphetamines and cocaine or other speed like drugs. Also severe infections or physiologic stress can it also.These are but a few.