What Causes Atrial Fibrillation?

Atrial fibrillation (AF) occurs when the electrical signals traveling through the heart are conducted abnormally and become very rapid and disorganized.

This is the result of damage to the heart's electrical system. The damage most often is the result of other conditions, such as coronary heart disease (also called coronary artery disease) or high blood pressure, that affect the health of the heart.

Sometimes, the cause of AF is unknown.