A heart murmur is an extra or unusual sound heard during a heartbeat. Murmurs range from very faint to very loud. Sometimes they sound like a whooshing or swishing noise.
Normal heartbeats make a "lub-DUPP" or "lub-DUB" sound. This is the sound of the heart valves closing as blood moves through the heart. Doctors can hear these sounds and heart murmurs using a stethoscope.
The two types of heart murmurs are innocent (harmless) and abnormal.
Innocent heart murmurs aren't caused by heart problems. These murmurs are common in healthy children. Many children will have heart murmurs heard by their doctors at some point in their lives.
People who have abnormal heart murmurs may have signs or symptoms of heart problems. Most abnormal murmurs in children are caused by congenital (kon-JEN-ih-tal) heart defects. These defects are problems with the heart's structure that are present at birth.
In adults, abnormal heart murmurs most often are caused by acquired heart valve disease. This is heart valve disease that develops as the result of another condition. Infections, diseases, and aging can cause heart valve disease.
A heart murmur isn't a disease, and most murmurs are harmless. Innocent murmurs don't cause symptoms. Having one doesn't require you to limit your physical activity or do anything else special. Although you may have an innocent murmur throughout your life, you won't need treatment for it.
The outlook and treatment for abnormal heart murmurs depend on the type and severity of the heart problem causing them.