Q: How frequent is atrial fibrillation?
A: Atrial fibrillation is the most common cardiac arrhythmia (about 0.5% in the general adult population). The risk of disease increases with age: in the over 65s, the percentage of people with AF rises to 5% or more. Rarely atrial fibrillation occurs in patients in whom the heart is structurally intact (that is, they have no other demonstrable heart disease). These cases represent approximately 10-15% of all atrial fibrillation patients and can be caused by genetic defects (mutations) and may present familial distribution (that is, this condition “runs in the family”). In most cases however the arrhythmia occurs in patients who have other cardiovascular diseases such as hypertension, coronary artery disease and diseases affecting the valves of the heart (valvular disease). For example, 30%-80% of patients who are operated on for mitral valve disease have atrial fibrillation. Atrial fibrillation also commonly occurs after all types of cardiac surgery. In these cases, if the diameter of the atria is normal, the arrhythmia almost always disappears after few days.