Many children have a heart murmur, especially during febrile illness.
When a heart murmur is detected during routine physical exam, a careful review of the child's appearance and history often provides clues about the murmur's significance. The classical innocent murmur is the vibratory systolic murmur referred to as Still's murmur. It is soft and of low frequency with a somewhat musical quality, like plucking a string or rubber band. Innocent murmurs often come and go. Also they may disappear if the child sits up or lies down.