Irregular heart beat
Depending on the individual's age and level of fitness, the heart beats (on average) between 60 and 100 times every minute. Almost everyone experiences a palpitation occasionally. This type of heart arrhythmia typically feels like a skipped beat, followed by a heavy thud.
A heart that persistently beats irregularly, too fast or too slow is considered to be experiencing heart arrhythmia, or abnormal heart rhythm. Many short-lived heart arrhythmias are caused by stress or emotional upset.
If palpitations are accompanied by fainting, lightheadedness or chest pain, you should seek urgent medical help.