Heart murmur

A heart murmur is an extra or unusual sound that occurs when your heart beats. These sounds can be heard with a stethoscope.

What causes heart murmurs?

As your heart beats, valves open and close to move blood through the heart. If a valve is defective, your heartbeat may include an extra or unusual noise known as a heart murmur. Some heart murmurs are faint, while others are quite loud.

A heart murmur is not necessarily a symptom of an underlying problem. Harmless (innocent) heart murmurs are fairly common in healthy children. Abnormal heart murmurs in children are usually a sign of a heart defect, such as problems with the interior walls of the heart muscle, valves, veins or arteries.

In adults, an abnormal heart murmur is usually caused by age-related changes or heart valve disease which develops as a result of another cardiac condition, such as:

  • Damage or scarring after a heart attack 
  • Heart failure
  • High blood pressure
  • Rheumatic fever
  • Infections in the heart

Symptoms of a heart murmur

A harmless heart murmur will not cause any other symptoms besides the unusual sound that can be heard when a doctor listens to your heart with a stethoscope.

An abnormal heart murmur is often a sign of another cardiac condition and may be one of many symptoms of that condition. Other warning signs to watch for include:

  • Shortness of breath
  • Skin that appears blue, especially on your fingertips and lips
  • Chest pain
  • Dizziness or fainting
  • Excessive sweating
  • Chronic cough
  • Enlarged neck veins
  • Enlarged liver
  • Poor appetite and failure to grow normally (in infants)

How are heart murmurs diagnosed?

Heart murmurs are often detected when your doctor listens to your heart with a stethoscope. Your doctor will listen to the volume, location and timing of the murmur to help determine what is causing it.

A few tests may help to determine the underlying cause of an abnormal heart murmur:

How are heart murmurs treated?

Because a heart murmur is not a disease in and of itself, it may not require treatment. In the case of an abnormal heart murmur, your doctor will treat the underlying disease or condition causing it. Treatment will vary depending on whether the abnormal heart murmur is caused by a congenital defect, heart valve disease, or another condition.