I was distraught to learn that my four-year-old son has a heart murmur. Our doctor says not to worry as it is almost certainly "innocent". What does this mean? Should he have x-rays and electrocardiograms to rule out a heart problem?
It is estimated that eight in 10 children aged three to six have heart murmurs at some time, often when they have a mild fever. These almost always disappear once the infection has subsided. Your doctor will have recognised this type of murmur. Echocardiography (using sound waves to show how the heart beats) will confirm the diagnosis, and reassure you that the murmur isn't linked to any other problem. X-rays and ECGs aren't nearly as useful, and are probably unnecessary. Murmurs that matter sound different, and are usually accompanied by other signs of heart disease, including becoming blue or breathless on exertion, failing to grow and having abnormal or absent pulses in the legs. If your son seems healthy, don't worry, and rely on your doctor's judgment.

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