palpitation (pălˌpĭtāˈshən) [key], abnormal heartbeat that is often associated with a sensation of fluttering or thumping. The normal heartbeat is not noticeable to the individual. Palpitation may be a symptom of organic heart disease or of other body disorders such as an overactive thyroid gland or anemia. In healthy persons palpitation can be brought on by undue exertion, shock, excitement, or stimulants.
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