Heart palpitations are a feeling that the heart is beating too hard or too fast, skipping a beat, or fluttering. You may notice heart palpitations in your chest, throat, or neck. Heart palpitations can be bothersome or frightening. They usually aren't serious or harmful, though, and often go away on their own. Most of the time, they're related to stress and anxiety or to consumption of stimulants such as caffeine, nicotine, or alcohol. Palpitations also often occur during pregnancy. In rare cases, palpitations can be a sign of a more serious heart condition. Therefore, if you have heart palpitations, make arrangements to see your doctor. And seek immediate medical attention if along with palpitations, you experience shortness of breath, dizziness, chest pain, or fainting.