Atrial fibrillation (A-fib) is an irregular and often very rapid heart rhythm (arrhythmia)
that can lead to blood clots in the heart. A-fib increases the risk of stroke, heart failure and other heart-related
Episodes of atrial fibrillation may come and go, or they may be persistent. Although A-fib itself usually isn't life-threatening,
Things that can cause an irregular heartbeat (arrhythmia) include: Current heart attack or scarring from a previous heart attack.