Any extra or unusual sounds other than the heart’s normal “lub-dub” beats are called heart murmurs. Heart murmurs in children are most commonly caused by turbulent flow in the heart. When doctors check for murmurs using a stethoscope, they come across as swishing or whooshing sounds.
Some children may have heart murmurs since birth (congenital), while some may develop it later due to different medical/non-medical conditions. Generally, children are more likely to have harmless heart murmurs that resolve themselves. Yet, it is essential to seek medical care to confirm that the sounds don’t indicate any underlying heart problems.
Keep reading to know more about the types, causes, signs, treatment, and prevention of heart murmurs in children.
Types Of Heart Murmurs
Heart murmurs can be of the following types (1).
- A systolic murmur is heard during the contraction of the heart.
- A diastolic murmur is heard during the relaxation of the heart.
- A continuous heart murmur is present throughout the heartbeat means during contraction and relaxation of the heart.
All heart murmurs are graded from 1 to 6 based on their audibility, where 1 is the least audible murmur, and 6 is the loudest murmur.
Causes Of Heart Murmurs In Children
Innocent murmurs are commonly seen in healthy children without any underlying problems. However, a few children could have pathologic heart murmurs due to structural or functional heart defects.
Common causes of murmurs may include (2):
- Anemia (low red blood cell count)
- Infections, such as endocarditis
- Hyperthyroidism (overactive thyroid)
- Heart valve diseases, such as stenosis or regurgitation
- Septal defects (holes in the heart)
- Rheumatic fever
Children with a positive family history of cardiac defects with unusual sounds could have an increased risk of developing murmurs. Physical activity and growth spurts in puberty are often the leading causes of innocent heart murmurs in children with normal hearts.
Signs And Symptoms Of Heart Murmurs In Children
No specific signs and symptoms are seen in children with innocent murmurs other than the abnormal heart sound heard on the stethoscope.
Children with pathological heart murmurs could have different signs and symptoms based on the underlying heart problems. The common signs and symptoms, along with heart murmurs, may include the following (3).
- Sweating (especially with feeding)
- Bluish skin, especially on fingertips and nails
- Poor weight gain
- Poor eating
- Chest pain
- Syncope (fainting due to sudden drop in the amount of blood supply to the heart)
- Edema or swelling of the ankle, legs, and other body parts
- Breathing problems, such as rapid or shallow breathing
- Trouble exercising
- Liver enlargement
- Enlarged neck veins
Some pathological heart murmurs may stay asymptomatic until the heart problems worsen. These symptoms can also be seen in other conditions, so consult a pediatrician for an exact diagnosis.
Diagnosis Of Heart Murmurs
Pediatricians may ask about the child’s health history and listen to the murmur through a stethoscope. If any abnormal heart sounds are noted during auscultation (listening via stethoscope), they refer the child to a pediatric cardiologist for further evaluation.
The following tests are often ordered to identify the cause of heart murmurs (4).
- Chest X-ray could help visualize the lungs and the size and shape of the heart.
- Echocardiography or echo is an imaging test that uses ultrasound to visualize the heart’s structure and functions. It may also help identify the type of murmur.
- Electrocardiography or ECG records the electrical activity of the heart. This helps to determine any conduction abnormalities of the heart causing murmurs.
Blood tests are not routinely done to look for cardiac problems, but if there is suspicion for infection, then it may be done. Additional tests in adults, such as cardiac catheterization and MRI scan, could also be performed based on the initial evaluation results.
Treatment For Heart Murmurs In Children
Treatment may vary depending on the cause, symptoms, and severity of heart murmurs. The child’s age and health status may also be taken into consideration. Innocent murmurs in healthy children do not require any specific treatment, and it resolves by itself over time (5).
In cases of pathological heart murmurs, treating the underlying cause could resolve the murmur in most children. Heart murmurs due to heart defects may require medications or cardiac surgery.
Possible Complications Of Heart Murmurs
Heart murmurs do not cause any complications. Children could get complications of the heart defects causing the murmur. Some heart defects are associated with poor growth and development in many children due to inadequate blood supply.
Significant heart defects could lead to heart failure and stroke. Early interventions to resolve the underlying causes of murmurs may help to avoid these complications (6).
Prevention Of Heart Murmurs In Children
Good prenatal care may help to prevent congenital heart defects in many children, thus the murmurs too. Maternal rubella vaccination and avoiding exposure to cigarettes, alcohol, and certain drugs during pregnancy could reduce the risk of cardiac defects that may cause murmur in children.
Valve pathologies are one of the significant causes of heart murmurs. Preventing rheumatic fever by treating strep throat on time could reduce the risk of murmurs in many children. Innocent murmurs are not preventable since it is related to the increased requirement of blood supply due to activity or growth spurts in children.
Your pediatrician may diagnose a heart murmur in your child when they auscultate the chest. As a parent, knowing about a murmur in your child’s heart may be worrisome. However, it may help to know that not all murmurs are due to a defect. Some murmurs occur due to no underlying cause and may resolve by themselves as they grow in age. If you notice any unusual symptoms such as excessive sweating, bluish discoloration of skin, fatigue, etc., you should consult your doctor. Get your child evaluated by a pediatric cardiologist to rule out any major complications. For families with a history of heart defects, you may ask your doctor for frequent preventive checkups for your child.
- Faster blood flow through the heart can cause an extra sound known as a heart murmur.
- In children, it is usually harmless and may be associated with conditions such as fever, infection, and anemia.
- Cough, poor eating, overtiredness, and chest pain are some of the many signs of heart murmurs.
- Treatment depends on the diagnosis and the age and health condition of the child.
2. Heart Murmurs In Children; The University of Rochester Medical Center
3. Heart Murmurs; St Louis Children’s Hospital
4. Heart Murmurs In Children; Children’s Hospital of Philadelphia
5. Heart Murmurs In Children; Healthychildren; The American Academy of Pediatrics
6. Heart Murmurs; Cedars-Sinai