common causes of atrial fibrillation
Causes of atrial fibrillation. The exact cause of atrial fibrillation is unknown, but it's more common with age and affects certain groups of people more than others. Atrial fibrillation is common in people with other heart conditions, such as: 1  high blood pressure (hypertension). 2  atherosclerosis.3  heart valve disease.4  congenital heart disease.auses of atrial fibrillation. The exact cause of atrial fibrillation is unknown, but it's more common with age and affects certain groups of people more than others. Atrial fibrillation is common in people with other heart conditions, such as: 1  high blood pressure (hypertension). 2  atherosclerosis.