5 Common Misconceptions about Heart Murmurs

5 Common Misconceptions about Heart Murmurs

1. A murmur is a hole in the heart.

FACT: A murmur is NOT a hole; a murmur is an extra heart SOUND. In addition to the normal “lub dub,” one may hear a swishing, blowing, whooshing or buzzing noise when listening to the heart with a stethoscope. This extra sound is called a murmur. Based on the location, quality, and volume of the sound, the provider will decide if your child should have a cardiac evaluation.

2. A murmur is a heart problem.

FACT: A murmur is NOT a type of heart problem. Most children with murmurs have normal, healthy hearts. If a child has an extra sound but their heart is structurally normal (meaning there are no holes, malfunctioning valves, abnormal connections, etc.), then the child has an innocent murmur. Innocent murmurs are VERY common in children and are caused by normal blood flow through the heart. For this reason, they are often referred to as “flow murmurs.”

A small proportion of children have abnormal murmurs. This is when an extra heart sound is caused a heart problem, such a hole in the heart or an abnormal valve. In these patients, the murmur is caused by flow turbulence through or near the abnormal structure. Because structural heart disease can be very serious, your child will have a cardiac evaluation if their provider hears an abnormal murmur.

In summary, some murmurs are CAUSED by heart problems, but a murmur is not a heart problem.

3. Murmurs run in families.

FACT: Murmurs do NOT run in families. Innocent murmurs are very common in children. Because all your adult family members were once children, there is a good chance that at least a few of them had murmurs when they were kids. Most innocent murmurs resolve in childhood, so it is very common to hear that someone in the family had a murmur that went away by itself.

With that said, not everyone knows the difference between a murmur and a heart defect, and sometimes lay people with use the word “murmur” to describe a heart problem. When someone tells me that murmurs run in their family, I ask more questions. Did anyone need to take medicine for their murmur? Did anyone need surgery or any other type of procedure to treat the murmur? Does this person see a cardiologist regularly? If the answer to any of these questions is yes, then that family member may actually have a history of structural heart disease, which is useful information to have when evaluating a patient.

4. I should be worried if my child’s innocent murmur does not go away with time.

FACT: An innocent murmur might NOT go away with time. The great thing about innocent murmurs is that they are benign. Insignificant. Harmless. These murmurs usually resolve by adolescence, but we still hear them in some teens and adults. Innocent murmurs often come and go, disappearing during part of childhood and reappearing during a time of rapid growth. Anything that makes the heartbeat faster or harder (such as fever, dehydration, anemia, or pregnancy) can make these murmurs louder.

There is one situation where a child previously diagnosed with an innocent murmur may require additional cardiac work up. A new, abnormal sounding murmur heard on exam could be a sign that something has changed within the heart. This does not mean that your child now has a hole their heart. Certain heart problems (like a hole in the heart or abnormal connection) are CONGENITAL meaning that they are present at birth and can be ruled out with a single echocardiogram. Other defects, such as thickening of the heart muscle or leakage of a heart valve can develop with time. If your provider suspects one of these lesions, your child may need additional testing (such as an electrocardiogram and/or echocardiogram).

5. Children with murmurs cannot play sports.

FACT: Most children with murmurs CAN play sports. Just because your child has a murmur does not necessarily mean their sports career is over. There are certain types of structural heart disease that can be dangerous in athletes, so those with new or suspicious murmurs are often referred for cardiac evaluation. Children with innocent murmurs have normal hearts, so they do not have sports restrictions. If your 4-year-old is diagnosed with an innocent murmur, feel free to support their dreams of Olympic glory.

Alisha Floyd, MD