The Infant or Child with a Heart Murmur

Written by Dr. Nauman Ahmad


Murmurs are either normal “physiologic” or abnormal “pathologic” heart sounds that are produced as a result of turbulent blood flow that is sufficient to produce audible noise. Most murmurs can only be heard with the assistance of a stethoscope ("on auscultation"). A functional murmur is also known as a "physiologic” or “innocent” murmur and is a sound that is primarily due to normal blood flow conditions through blood vessels and in the heart, and is by definition not due to structural defects in the heart. They are the most common murmurs and are benign or normal. It is also normal that this murmur may be more prominent when the heart rate is faster such as in situations of patient anxiety, exercise, anemia or fever. There is no associated increased risk for cardiac problems in other family members because of such a physiological murmur. The health implications are good in innocent murmurs.

Murmurs may also originate from various congenital or birth problems, such as narrowing or leaking of valves, or the presence of abnormal passages through which blood flows within or near the heart. Such murmurs are known as “pathologic” murmurs and should be evaluated by a specialized and experienced physician known as a Pediatric Cardiologist. This pediatric cardiologist evaluates the location, character, timing, radiation and amplitude (grade) of the murmur. To help confirm if there is a possible heart condition a special ultrasound known as an echocardiogram may be used to reach a final diagnosis. The health implications vary depending on the type of heart defect identified through examination and echocardiography.