Pediatric Heart Murmurs

Murmurs are sounds made by blood circulating through the heart's chambers or valves, or through blood vessels near the heart. 

Heart murmurs may be caused by a number of factors or diseases, including the following:

• Defective heart valves
• Holes in the heart walls
• Surgical repair of congenital (present at birth) heart defects
• Fever
• Anemia (a decrease in the red cells in the blood)

Your child's physician will evaluate a murmur based on several factors. Murmurs are analyzed for pitch, loudness and duration. They also are graded according to their intensity (on a scale of one to six, with one being very faint and six being very loud).

Types of murmurs include the following:

• Systolic murmur. A heart murmur that occurs during a heart muscle contraction. Systolic murmurs are divided into ejection murmurs (due to blood flow through a narrowed vessel or irregular valve) and regurgitant murmurs.
• Diastolic murmur. A heart murmur that occurs during heart muscle relaxation between beats. Diastolic murmurs are due to a narrowing of the mitral or tricuspid valves, or regurgitation of the aortic or pulmonary valves.
• Continuous murmur. A heart murmur that occurs throughout the cardiac cycle. Murmurs related to a congenital (present at birth) heart defect or other problem involving the heart structures will be heard the loudest in the area of the chest where the problem occurs.

Children with innocent murmurs have no other symptoms except the abnormal heart sounds. A child with a pathologic heart murmur may have 1 or more of the following symptoms. They vary depending on the problem.

In babies:

• Feeding difficulties (sweating while feeding), skin or lips have bluish tinge (cyanosis) during feeding or activity.
• Poor feeding, weight gain, failure to thrive.
• Shortness of breath or breathing fast.
• Sweating.

In children:

• Chest pain on exertion.
• Dizziness or fainting (syncope).
• Palpitations.
• Bluish skin, especially on the lips and fingertips.
• Cough.
• Swelling (edema) of the lower legs, ankles, feet, belly (abdomen), liver, or neck veins.

The symptoms of heart murmur can be like other health conditions. Have your child see their health care provider for a diagnosis.

The provider will ask about your child’s symptoms and health history. They will do a physical exam on your child. During an exam, the provider will listen to your child's heart with a stethoscope. If the provider hears an abnormal sound, they may refer you to a pediatric cardiologist. This is a doctor with special training to treat children with heart problems. Tests include:

• Chest X-ray.  An X-ray creates images of the heart and lungs.
• Electrocardiogram (ECG). This test measures the electrical activity of the heart.
• Echocardiography (echo). This exam uses sound waves (ultrasound) to look at the structure and function of the heart. This is the most important test to find heart murmurs.

Treatment will depend on your child’s symptoms, age, and general health. It will also depend on how severe the condition is.

Many heart murmurs are normal, extra sounds in children with strong, healthy hearts. These children don’t need treatment. Some of these heart murmurs may go away on their own with time.

If the murmur is from a congenital heart defect, treatment may include medicine, procedures, or surgery. If the murmur is from another condition, the heart murmur will usually lessen or go away once the condition is treated.

Not all heart murmurs are symptoms of heart disease. Sometimes, a murmur may be heard in a normal child who has a fever or who is anemic; these murmurs often go away when the underlying problem is treated.

Some children have what is known as an innocent murmur. These murmurs are not related to congenital heart defects, and usually resolve by the time a child reaches adulthood. If your child's physician hears an innocent murmur, he/she may want to perform additional tests to ensure a heart defect is not present. A child with an innocent murmur can live a normal life and be as active as any other healthy child.