About Atrial Fibrillation
This is the classic “irregular heart rhythm,” though there are many other heart rhythms besides atrial fibrillation that are irregular. In atrial fibrillation, the upper chambers (“atria”) have electrical signals that occur so fast that the atria can’t actually beat—they just quiver (fibrillate). Most impulses are filtered out before they travel down to the main pumping chambers (the “ventricles”), so atrial fibrillation doesn’t lead to ventricular fibrillation (a very different—and lethal—heart rhythm). The main risk of atrial fibrillation is having a stroke, so we often put people on blood thinners to lower that risk.