Most people experience a change in their heartbeats, so the condition is very common.
But in extreme cases, when the fibers that carry electrical impulses through the heart become damaged, a serious, life-threatening condition occurs. Sometimes, sudden cardiac death can result in these patients. Patients with arrhythmia often complain of a rapid heartbeat or dizziness. A physical examination can often help doctors find arrhythmia before it becomes serious. Doctors may use an electrocardiogram or a monitor that is worn for a 24-hour period to determine the seriousness of symptoms.