Atrial fibrillation (also called AFib or AF) may be a quivering or irregular heartbeat (arrhythmia) which will cause blood clots, stroke, coronary failure and other heart-related complications. a minimum of 2.7 million Americans live with AFib. Abnormalities or damage to the heart's structure are the foremost common explanation for fibrillation . Possible causes of fibrillation include: High vital sign . attack . Ideally, to treat fibrillation , the guts rate and rhythm are reset to normal. To correct your condition, doctors could also be ready to reset your heart to its regular rhythm (sinus rhythm) employing a procedure called cardioversion, counting on the underlying explanation for fibrillation and the way long you've had it.