Atrial fibrillation (AF), the most common cardiac arrhythmia, is characterized by erratic beating of the heart’s upper chambers (atria), often leading to a very rapid heart rate and impeding blood flow from the atria into the lower chambers of the heart (ventricles).  This lack of mechanical contraction in the atria can lead to pooling of blood, increasing the risk of clot formation and embolism with stroke if the clot breaks loose and travels to the brain.

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