A heart murmur in a child is an extra sound heard during a heartbeat, distinct from the typical “lub-dub” rhythm. This whooshing or swishing noise occurs when blood flow through the heart is turbulent. While the term may sound concerning, many heart murmurs in children are common and harmless, not indicating a serious underlying heart problem.
Understanding Different Types
Heart murmurs in children fall into two main categories: innocent (or functional) murmurs and pathological (or organic) murmurs. The distinction between these types is important for determining the murmur’s seriousness and the need for further medical attention.
Innocent heart murmurs are the most common type, occurring in over two-thirds of school-aged children. They are not caused by heart defects but are simply the sound of normal blood flowing through a healthy, developing heart. These harmless murmurs often disappear as a child grows and require no treatment or activity restrictions. An innocent murmur might become louder with fever, excitement, or stress, but this does not indicate a problem.
In contrast, pathological heart murmurs are less common, signifying an underlying heart condition. Occurring in less than 1% of the population, these murmurs warrant further evaluation. They are often louder, may include an extra “clicking” sound, and can radiate to other body parts like the back, helping doctors differentiate them from innocent murmurs.
When a Murmur Indicates a Problem
A pathological heart murmur indicates an issue with the heart’s structure or function, creating turbulent blood flow. Most often, these are linked to congenital heart defects, problems present at birth. Examples include holes in the heart walls (e.g., VSD, ASD) allowing abnormal blood flow, or valve abnormalities (e.g., stenosis, regurgitation) where blood struggles to pass or flows backward. Conditions like patent ductus arteriosus (PDA), where a blood vessel fails to close after birth, can also cause a continuous murmur.
Other conditions can also contribute to a pathological murmur. These include hypertrophic cardiomyopathy, where thickened heart muscle impedes blood flow. Certain medical conditions like severe anemia, fever, or hyperthyroidism can also cause temporary murmurs due to increased blood flow, resolving once the underlying condition is treated.
Unlike innocent murmurs, pathological murmurs can be accompanied by other symptoms indicating a heart problem. These include poor feeding, inadequate weight gain, rapid breathing, shortness of breath, excessive sweating, bluish skin or lips (cyanosis), chest pain, or dizziness during physical activity. The presence of these symptoms prompts a more thorough medical investigation.
How Doctors Evaluate Murmurs
Doctors evaluate a child’s heart murmur with a thorough physical examination. This involves listening carefully to the heart with a stethoscope to assess the murmur’s loudness, pitch, and timing. The doctor also notes where the murmur is loudest and if it spreads to other areas like the back or neck. They will also check the child’s overall appearance, pulse, and blood pressure.
If the physical examination suggests a pathological murmur, additional diagnostic tests are ordered to identify the underlying cause and severity. The most common test is an echocardiogram, which uses sound waves to create detailed images of the heart’s structure and blood flow. This ultrasound can detect structural abnormalities like holes or valve problems. An electrocardiogram (ECG or EKG) may also measure the heart’s electrical activity, identifying abnormal rhythms or strain. A chest X-ray can provide an image of the heart and lungs, revealing enlargement or fluid, which can be associated with certain heart conditions.
Managing a Child’s Heart Murmur
Management of a child’s heart murmur depends entirely on its type. If identified as innocent, no medical treatment or intervention is necessary. These murmurs often resolve as the child grows, and children can participate in all normal activities, including sports, without restriction.
For pathological heart murmurs, management focuses on the specific underlying condition causing the sound. Treatment options vary widely based on the diagnosis and its severity. For mild conditions, regular monitoring by a pediatric cardiologist may be sufficient to track the heart’s health over time.
Some conditions might require medication to manage symptoms, improve heart function, or prevent complications. In more severe cases of structural defects, surgical intervention or catheter-based procedures might be necessary to repair the heart defect. Despite the need for medical management, many children with pathological murmurs can lead full and active lives with appropriate care and follow-up.