Heart palpitations are the feelings of having rapid, fluttering or pounding heartbeats. Its a feelings that the heart is skipping a beat, or beating too hard or too fast. These feelings may be in the chest, throat or neck. It can occur during activity or even when sitting still or lying down. Palpitations are very common, usually aren't serious or harmful. They may also be a symptom of a more serious heart condition, such as an irregular heartbeat(arrhythmia), that may require treatment.
Attribution: Straight Talk Foundation