What is Atrial Fibrillation?
The heart has an electrical system, which provides signals to the chambers of the heart indicating when they should contract (squeeze) or relax. Atrial Fibrillation (Afib) is caused by chaotic electrical signals, which make the upper chambers of the heart (the atria) quiver, instead of fully contracting. For someone with AFib, the atria may beat as often as 300 times a minute, about four times faster than normal. Blood can pool in the atria during AFib, which can allow a clot to form. If a blood clot dislodges from the atria, it can cause a stroke.