Heart murmurs in pediatric patients is not a serious condition, says physician

Jan 23 2010

Your 3-year-old's doctor discovers a heart murmur during a visit for a mild cold with fever and recommends referral to a pediatric cardiologist. You worry and wonder how your healthy, active child could possibly have a heart problem.

"Finding out that your child has a heart murmur causes a great deal of anxiety," said Dr. Louis Bezold, associate professor of pediatrics and chief of the division of pediatric cardiology, University of Kentucky College of Medicine, and co-director of the Kentucky Children's Heart Center. "It is a common misconception that all murmurs are serious, but this is not the case.

Murmurs are actually extremely common findings in infants and children. In fact, most children will have a murmur at some point during childhood.

According to Bezold, a murmur is simply an extra noise in addition to the normal heart sounds (so-called "lub-dub") heard using a stethoscope. When your doctor listens to your child's heart they will note the location, intensity and other characteristics of the extra sound. Based on the examination, murmurs can be classified in two broad categories: innocent or pathologic.

Innocent murmurs (also known as benign, functional or flow murmurs) are the most common. As their name implies, they are not considered abnormal and have no effect on a child's health. Most innocent murmurs disappear at some point during infancy or childhood. Children with innocent murmurs require no medications or restrictions on activity or diet. In fact, regular physical activity and a healthy diet are very important for heart health. An innocent murmur is not a heart condition.

On the other hand, a pathologic murmur indicates a heart abnormality, including congenital heart defects (present at birth) or heart muscle functional problems. Pathologic murmurs are less common; for example, only about one to two percent of babies are born with a structural heart defect.

Some infants will exhibit signs of a problem early in life. However, some heart defects are detected only because a murmur is noted during childhood. Symptoms that can indicate a heart problem in infancy include feeding problems, fast breathing, poor weight gain and blueness of the tongue or inside of the mouth. Older children may have excessive fatigue or chest pain with physical exertion.

Some pathologic murmurs are due to relatively minor problems that may resolve spontaneously. Treatment for more significant defects may involve medications, antibiotics for dental work, activity restrictions and/or more definitive treatment via surgery or heart catheterization. Fortunately, highly successful potential therapies now exist for most pediatric heart problems.
It is fairly common for a "new" murmur to be noted during a check-up.

Innocent murmurs tend to be louder in certain situations such as with fever or after crying. Very quiet murmurs can go undetected until the child is old enough to be cooperative enough for your doctor to hear. However, some pathologic murmurs initially may not be audible, but will become louder if the condition worsens over time. Also, although some loud murmurs suggest more serious problems, loud doesn't necessarily mean bad: the tiniest holes in the heart cause the loudest murmurs, but are generally of little consequence with respect to a child's health and often spontaneously close.
Evaluation of heart murmurs by a pediatric cardiologist will include a thorough physical examination and may include other tests such as a chest x-ray, electrocardiogram (ECG) and/or an echocardiogram. Some murmurs can be classified as innocent by examination alone. An echocardiogram is an ultrasound examination which provides moving images of the structure and function of the heart, allowing detection of congenital defects and other heart problems. After the evaluation is complete the doctor will go over the findings and explain in detail what your child's murmur means.

"In many cases, this will be good news, but even if the murmur is pathologic your pediatric cardiologist can still provide good treatment options for your child," Bezold said.

Source: University of Kentucky College of Medicine