September is Atrial Fibrillation Awareness Month. Atrial fibrillation may be a familiar enough term—you probably know that it has to do with the heart, for example—but you may not know exactly what it means.

Atrial fibrillation is commonly shortened to AFib. It is a change in heart rhythm in which the upper and lower chambers of the heart beat out of sync—it can lead to stroke, heart failure, or other heart-related problems. [1]