Benign paediatric heart murmur

A benign paediatric heart murmur, also innocent heart murmur or innocent murmur, is an inconsequential sound that originate from the heart and/or cardiovascular system and is heard on cardiac auscultation. By definition, an innocent murmur is not significant in the long-term health of an individual that has it.

Murmurs - innocent versus pathological
Characteristics of innocent murmurs are:
 * Less than 3/6 in intensity, soft
 * Often position-dependent (supine versus upright)
 * Otherwise healthy individual, no concerns about growth
 * Continuous (throughout cardiac cycle) or systolic (diastolic-only sounds are always pathologic)
 * Normal S2 splitting (S2 splitting with inspiration)
 * No palpable thrill (vibration of the chest due to abnormal heart movement/blood flow)

Prognosis
Innocent murmurs are inconsequential and usually disappear as the child grows. ECG and Chest XRAY are normal.

Types, description and DDx
LLSB = lower left sternal border