What is the difference between atrial fibrillation (AFib) and atrial flutter?

Atrial fibrillation (AFib) and atrial flutter are both types of irregular heart rhythms that originate in the upper chambers of the heart (atria). The main difference between the two is the pattern of the abnormal heartbeats. In AFib, the heartbeats are irregular and chaotic, while in atrial flutter, the heartbeats are typically more organized and rapid. Both conditions can increase the risk of complications like stroke and heart failure, so it's important to seek medical attention if you experience symptoms of either condition.