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general::
Also, one's heart skips a beat or stands still. One is startled, frightened, or very excited. For example, Her heart missed a beat when she heard her name called out in the list of finalists, or When the bear appeared in front of us, my heart skipped a beat, or My heart stands still at the very thought of flying through a thunderstorm. All these hyperbolic expressions can Also be used with make, meaning "to cause one to be startled" as in That blast from the ship's whistle made my heart skip a beat.
American Heritage Idioms