An arrhythmia, or irregular heartbeat, is a problem with the rate or rhythm of your heartbeat Your heart may beat too quickly, too slowly, or with an irregular rhythm It is normal for your heart rate to speed up during physical activity and to slow down while resting or sleeping It is also normal to feel as if your heart skips a beat occasionally But a frequent irregular rhythm may mean that your heart is not pumping enough blood to your body You may feel dizzy, faint, or have other If you have been diagnosed with an arrhythmia, your doctor may talk to you about healthy lifestyle changes you can make You may need to avoid activities that may trigger your arrhythmia These steps may help prevent your arrhythmia from getting worse