What is a normal heartbeat?ĭoctors identify a healthy heartbeat by counting the number of times the heart beats every minute (bpm) during rest. irregular heartbeat, also known as a flutter or fibrillation, such as atrial fibrillation (A-fib)Īrrhythmias are not always serious, but some can increase the risk of stroke or cardiac arrest.Share on Pinterest Carol Yepes/Getty ImagesĬardiac arrhythmia refers to conditions in which the heart beats irregularly, too slowly, or too quickly.