A heart murmur is an extra or unusual sound heard during a heartbeat. Murmurs range from quite faint to very loud.
- There are two types of heart murmurs: innocent (harmless) and abnormal.
- People who have innocent heart murmurs have normal hearts. They usually have no other signs or symptoms of heart problems.
- People who have abnormal murmurs may have other signs or symptoms of heart problems. Most abnormal murmurs in children are due to congenital (present at birth) heart defects.