What causes heart murmurs?
Abnormal heart murmurs in adults are related to defective heart valves. Some heart murmurs are not considered to be a problem and may be referred to as “innocent murmurs.” Abnormal heart murmurs in adults may be related to:
Not every murmur is associated with valve disease. Murmurs can also be caused by conditions that may temporarily increase blood flow such as:
- Rapid growth spurts in children
Your healthcare provider will probably investigate the root cause of the heart murmur. Clues about the cause can be explored based on how loud the sound is, graded from 1 to 6. A grade of 1 out of 6 (1/6) is very faint, heard only with a special effort. A grade 6 out of 6 (6/6) is extremely loud, and can be heard with a stethoscope even when slightly removed from the chest.
The doctor will check where the murmur is in your heart, duration, and when the murmur is heard during the heartbeat. Short, quiet murmurs may be more likely to be benign (meaning they are harmless and no treatment is needed.)
Other tests your doctor may use to decide if the murmur is abnormal include:
As with most conditions, heart murmurs and any underlying problems will vary in severity and risk.
Seeking a Qualified Healthcare Provider or Specialist
Any time a murmur is suspected to be associated with a valve problem that may eventually need treatment or repair, it is wise to begin investigating your community for a qualified healthcare provider with experience at diagnosing and treating your heart condition.
If you are unsure about your risks, it is always appropriate to ask your primary healthcare provider whether or not they have broad experience with diagnosing and treating heart valve problems. When in question, a specialist who regularly deals with valve disease can give you your best assessment, and many healthcare providers may choose to bring in a specialist to the team.
This content was last reviewed May 2016.