Atrial Fibrillation - Afib
Atrial fibrillation, sometimes called "Afib", is the most prevalent type of heart arrhythmia (abnormal heart rhythm) and affects more than 4 million people in the U.S. With atrial fibrillation, the heart's upper chambers beat irregularly, affecting blood flow to the heart muscle and to the rest of the body. This can cause blood clots leading to a stroke.