Murmur occurs when there is turbulent blood flow. Innocent murmurs are quite common in children due to the high velocity of blood flow. Operation is not for the murmur, but for the heart disease which causes it. Only if the heart disease which causes the murmur is severe enough does it require an operation, not otherwise. So the first thing is to verify the cause of the murmur with your doctor. If it is due to heart disease, further investigations like an ECG, X-ray and echocardiogram are needed while deciding whether operation is required.