An arrhythmia is an occasional or consistent problem with the rhythm or rate of your heartbeat. Your heart may be beating too fast, too slow, or beating with an irregular rhythm. During an arrhythmia, some people may feel a fluttering in their chest or that their heart is suddenly racing.
Fatigue, lightheadedness or fainting may also be symptoms of an arrhythmia. Some arrhythmias do not cause any symptoms. There are many types of arrhythmias. Some arrhythmias are harmless, but some can be serious or even life-threatening. If an arrhythmia is severe or lasts long enough to affect how the heart works, it may prevent the heart from pumping enough blood to the body.
Even serious arrhythmias can be successfully treated. Before treatment your doctor must first determine where in the heart an arrhythmia may be happening and whether or not it is abnormal.