Atrial fibrillation, often abbreviated as AF, is a common type of cardiac arrhythmia in the elderly. Medically, it is described as a disorderly and irregular heart rhythm without a rhythm in the atria. In layman's terms, for example, if our heartbeat is like people queuing up to buy tickets, normally everyone comes one by one in an orderly manner. Atrial fibrillation, however, is like everyone rushing to the ticketing area at once. Consequently, some people might run fast, others slow, some take up more space because they are heavier, and others less because they are thinner. Atrial fibrillation is similar to this scenario.